/*----------------------------------------------------------------------------/
/  FatFs - FAT file system module  R0.09                  (C)ChaN, 2011
/-----------------------------------------------------------------------------/
/ FatFs module is a generic FAT file system module for small embedded systems.
/ This is a free software that opened for education, research and commercial
/ developments under license policy of following terms.
/
/  Copyright (C) 2011, ChaN, all right reserved.
/
/ * The FatFs module is a free software and there is NO WARRANTY.
/ * No restriction on use. You can use, modify and redistribute it for
/   personal, non-profit or commercial products UNDER YOUR RESPONSIBILITY.
/ * Redistributions of source code must retain the above copyright notice.
/
/-----------------------------------------------------------------------------/
/ Feb 26,'06 R0.00  Prototype.
/
/ Apr 29,'06 R0.01  First stable version.
/
/ Jun 01,'06 R0.02  Added FAT12 support.
/                   Removed unbuffered mode.
/                   Fixed a problem on small (<32M) partition.
/ Jun 10,'06 R0.02a Added a configuration option (_FS_MINIMUM).
/
/ Sep 22,'06 R0.03  Added f_rename().
/                   Changed option _FS_MINIMUM to _FS_MINIMIZE.
/ Dec 11,'06 R0.03a Improved cluster scan algorithm to write files fast.
/                   Fixed f_mkdir() creates incorrect directory on FAT32.
/
/ Feb 04,'07 R0.04  Supported multiple drive system.
/                   Changed some interfaces for multiple drive system.
/                   Changed f_mountdrv() to f_mount().
/                   Added f_mkfs().
/ Apr 01,'07 R0.04a Supported multiple partitions on a physical drive.
/                   Added a capability of extending file size to f_lseek().
/                   Added minimization level 3.
/                   Fixed an endian sensitive code in f_mkfs().
/ May 05,'07 R0.04b Added a configuration option _USE_NTFLAG.
/                   Added FSInfo support.
/                   Fixed DBCS name can result FR_INVALID_NAME.
/                   Fixed short seek (<= csize) collapses the file object.
/
/ Aug 25,'07 R0.05  Changed arguments of f_read(), f_write() and f_mkfs().
/                   Fixed f_mkfs() on FAT32 creates incorrect FSInfo.
/                   Fixed f_mkdir() on FAT32 creates incorrect directory.
/ Feb 03,'08 R0.05a Added f_truncate() and f_utime().
/                   Fixed off by one error at FAT sub-type determination.
/                   Fixed btr in f_read() can be mistruncated.
/                   Fixed cached sector is not flushed when create and close without write.
/
/ Apr 01,'08 R0.06  Added fputc(), fputs(), fprintf() and fgets().
/                   Improved performance of f_lseek() on moving to the same or following cluster.
/
/ Apr 01,'09 R0.07  Merged Tiny-FatFs as a configuration option. (_FS_TINY)
/                   Added long file name feature.
/                   Added multiple code page feature.
/                   Added re-entrancy for multitask operation.
/                   Added auto cluster size selection to f_mkfs().
/                   Added rewind option to f_readdir().
/                   Changed result code of critical errors.
/                   Renamed string functions to avoid name collision.
/ Apr 14,'09 R0.07a Separated out OS dependent code on reentrant cfg.
/                   Added multiple sector size feature.
/ Jun 21,'09 R0.07c Fixed f_unlink() can return FR_OK on error.
/                   Fixed wrong cache control in f_lseek().
/                   Added relative path feature.
/                   Added f_chdir() and f_chdrive().
/                   Added proper case conversion to extended char.
/ Nov 03,'09 R0.07e Separated out configuration options from ff.h to ffconf.h.
/                   Fixed f_unlink() fails to remove a sub-dir on _FS_RPATH.
/                   Fixed name matching error on the 13 char boundary.
/                   Added a configuration option, _LFN_UNICODE.
/                   Changed f_readdir() to return the SFN with always upper case on non-LFN cfg.
/
/ May 15,'10 R0.08  Added a memory configuration option. (_USE_LFN = 3)
/                   Added file lock feature. (_FS_SHARE)
/                   Added fast seek feature. (_USE_FASTSEEK)
/                   Changed some types on the API, XCHAR->TCHAR.
/                   Changed fname member in the FILINFO structure on Unicode cfg.
/                   String functions support UTF-8 encoding files on Unicode cfg.
/ Aug 16,'10 R0.08a Added f_getcwd(). (_FS_RPATH = 2)
/                   Added sector erase feature. (_USE_ERASE)
/                   Moved file lock semaphore table from fs object to the bss.
/                   Fixed a wrong directory entry is created on non-LFN cfg when the given name contains ';'.
/                   Fixed f_mkfs() creates wrong FAT32 volume.
/ Jan 15,'11 R0.08b Fast seek feature is also applied to f_read() and f_write().
/                   f_lseek() reports required table size on creating CLMP.
/                   Extended format syntax of f_printf function.
/                   Ignores duplicated directory separators in given path names.
/
/ Sep 06,'11 R0.09  f_mkfs() supports multiple partition to finish the multiple partition feature.
/                   Added f_fdisk(). (_MULTI_PARTITION = 2)
/---------------------------------------------------------------------------*/

#include "ff.h"     /* FatFs configurations and declarations */
#include "diskio.h"   /* Declarations of low level disk I/O functions */


/*--------------------------------------------------------------------------

   Module Private Definitions

---------------------------------------------------------------------------*/

#if _FATFS != 6502  /* Revision ID */
#error Wrong include file (ff.h).
#endif


/* Definitions on sector size */
#if _MAX_SS != 512 && _MAX_SS != 1024 && _MAX_SS != 2048 && _MAX_SS != 4096
#error Wrong sector size.
#endif
#if _MAX_SS != 512
#define SS(fs)  ((fs)->ssize) /* Variable sector size */
#else
#define SS(fs)  512U      /* Fixed sector size */
#endif


/* Reentrancy related */
#if _FS_REENTRANT
#if _USE_LFN == 1
#error Static LFN work area must not be used in re-entrant configuration.
#endif
#define ENTER_FF(fs)    { if (!lock_fs(fs)) return FR_TIMEOUT; }
#define LEAVE_FF(fs, res) { unlock_fs(fs, res); return res; }
#else
#define ENTER_FF(fs)
#define LEAVE_FF(fs, res) return res
#endif

#define ABORT(fs, res)    { fp->flag |= FA__ERROR; LEAVE_FF(fs, res); }


/* File shareing feature */
#if _FS_SHARE
#if _FS_READONLY
#error _FS_SHARE must be 0 on read-only cfg.
#endif
typedef struct {
  FATFS *fs;        /* File ID 1, volume (NULL:blank entry) */
  DWORD clu;        /* File ID 2, directory */
  WORD idx;       /* File ID 3, directory index */
  WORD ctr;       /* File open counter, 0:none, 0x01..0xFF:read open count, 0x100:write mode */
} FILESEM;
#endif


/* Misc definitions */
#define LD_CLUST(dir) (((DWORD)LD_WORD(dir+DIR_FstClusHI)<<16) | LD_WORD(dir+DIR_FstClusLO))
#define ST_CLUST(dir,cl) {ST_WORD(dir+DIR_FstClusLO, cl); ST_WORD(dir+DIR_FstClusHI, (DWORD)cl>>16);}


/* DBCS code ranges and SBCS extend char conversion table */

#if _CODE_PAGE == 932 /* Japanese Shift-JIS */
#define _DF1S 0x81  /* DBC 1st byte range 1 start */
#define _DF1E 0x9F  /* DBC 1st byte range 1 end */
#define _DF2S 0xE0  /* DBC 1st byte range 2 start */
#define _DF2E 0xFC  /* DBC 1st byte range 2 end */
#define _DS1S 0x40  /* DBC 2nd byte range 1 start */
#define _DS1E 0x7E  /* DBC 2nd byte range 1 end */
#define _DS2S 0x80  /* DBC 2nd byte range 2 start */
#define _DS2E 0xFC  /* DBC 2nd byte range 2 end */

#elif _CODE_PAGE == 936 /* Simplified Chinese GBK */
#define _DF1S 0x81
#define _DF1E 0xFE
#define _DS1S 0x40
#define _DS1E 0x7E
#define _DS2S 0x80
#define _DS2E 0xFE

#elif _CODE_PAGE == 949 /* Korean */
#define _DF1S 0x81
#define _DF1E 0xFE
#define _DS1S 0x41
#define _DS1E 0x5A
#define _DS2S 0x61
#define _DS2E 0x7A
#define _DS3S 0x81
#define _DS3E 0xFE

#elif _CODE_PAGE == 950 /* Traditional Chinese Big5 */
#define _DF1S 0x81
#define _DF1E 0xFE
#define _DS1S 0x40
#define _DS1E 0x7E
#define _DS2S 0xA1
#define _DS2E 0xFE

#elif _CODE_PAGE == 437 /* U.S. (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x9A,0x90,0x41,0x8E,0x41,0x8F,0x80,0x45,0x45,0x45,0x49,0x49,0x49,0x8E,0x8F,0x90,0x92,0x92,0x4F,0x99,0x4F,0x55,0x55,0x59,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0x41,0x49,0x4F,0x55,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 720 /* Arabic (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x45,0x41,0x84,0x41,0x86,0x43,0x45,0x45,0x45,0x49,0x49,0x8D,0x8E,0x8F,0x90,0x92,0x92,0x93,0x94,0x95,0x49,0x49,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 737 /* Greek (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x92,0x92,0x93,0x94,0x95,0x96,0x97,0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87, \
        0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0xAA,0x92,0x93,0x94,0x95,0x96,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0x97,0xEA,0xEB,0xEC,0xE4,0xED,0xEE,0xE7,0xE8,0xF1,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 775 /* Baltic (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x9A,0x91,0xA0,0x8E,0x95,0x8F,0x80,0xAD,0xED,0x8A,0x8A,0xA1,0x8D,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0x95,0x96,0x97,0x97,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9F, \
        0xA0,0xA1,0xE0,0xA3,0xA3,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xB5,0xB6,0xB7,0xB8,0xBD,0xBE,0xC6,0xC7,0xA5,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE3,0xE8,0xE8,0xEA,0xEA,0xEE,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 850 /* Multilingual Latin 1 (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xB7,0x8F,0x80,0xD2,0xD3,0xD4,0xD8,0xD7,0xDE,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0xE3,0xEA,0xEB,0x59,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9F, \
        0xB5,0xD6,0xE0,0xE9,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE7,0xE7,0xE9,0xEA,0xEB,0xED,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 852 /* Latin 2 (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xDE,0x8F,0x80,0x9D,0xD3,0x8A,0x8A,0xD7,0x8D,0x8E,0x8F,0x90,0x91,0x91,0xE2,0x99,0x95,0x95,0x97,0x97,0x99,0x9A,0x9B,0x9B,0x9D,0x9E,0x9F, \
        0xB5,0xD6,0xE0,0xE9,0xA4,0xA4,0xA6,0xA6,0xA8,0xA8,0xAA,0x8D,0xAC,0xB8,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBD,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC6,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD1,0xD1,0xD2,0xD3,0xD2,0xD5,0xD6,0xD7,0xB7,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE3,0xD5,0xE6,0xE6,0xE8,0xE9,0xE8,0xEB,0xED,0xED,0xDD,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xEB,0xFC,0xFC,0xFE,0xFF}

#elif _CODE_PAGE == 855 /* Cyrillic (OEM) */
#define _DF1S 0
#define _EXCVT {0x81,0x81,0x83,0x83,0x85,0x85,0x87,0x87,0x89,0x89,0x8B,0x8B,0x8D,0x8D,0x8F,0x8F,0x91,0x91,0x93,0x93,0x95,0x95,0x97,0x97,0x99,0x99,0x9B,0x9B,0x9D,0x9D,0x9F,0x9F, \
        0xA1,0xA1,0xA3,0xA3,0xA5,0xA5,0xA7,0xA7,0xA9,0xA9,0xAB,0xAB,0xAD,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB6,0xB6,0xB8,0xB8,0xB9,0xBA,0xBB,0xBC,0xBE,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD1,0xD1,0xD3,0xD3,0xD5,0xD5,0xD7,0xD7,0xDD,0xD9,0xDA,0xDB,0xDC,0xDD,0xE0,0xDF, \
        0xE0,0xE2,0xE2,0xE4,0xE4,0xE6,0xE6,0xE8,0xE8,0xEA,0xEA,0xEC,0xEC,0xEE,0xEE,0xEF,0xF0,0xF2,0xF2,0xF4,0xF4,0xF6,0xF6,0xF8,0xF8,0xFA,0xFA,0xFC,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 857 /* Turkish (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xB7,0x8F,0x80,0xD2,0xD3,0xD4,0xD8,0xD7,0x98,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0xE3,0xEA,0xEB,0x98,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9E, \
        0xB5,0xD6,0xE0,0xE9,0xA5,0xA5,0xA6,0xA6,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xDE,0x59,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 858 /* Multilingual Latin 1 + Euro (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x9A,0x90,0xB6,0x8E,0xB7,0x8F,0x80,0xD2,0xD3,0xD4,0xD8,0xD7,0xDE,0x8E,0x8F,0x90,0x92,0x92,0xE2,0x99,0xE3,0xEA,0xEB,0x59,0x99,0x9A,0x9D,0x9C,0x9D,0x9E,0x9F, \
        0xB5,0xD6,0xE0,0xE9,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC7,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD1,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE5,0xE5,0xE6,0xE7,0xE7,0xE9,0xEA,0xEB,0xED,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 862 /* Hebrew (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0x41,0x49,0x4F,0x55,0xA5,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0x21,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 866 /* Russian (OEM) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0x90,0x91,0x92,0x93,0x9d,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F,0xF0,0xF0,0xF2,0xF2,0xF4,0xF4,0xF6,0xF6,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 874 /* Thai (OEM, Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 1250 /* Central Europe (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x8A,0x9B,0x8C,0x8D,0x8E,0x8F, \
        0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xA3,0xB4,0xB5,0xB6,0xB7,0xB8,0xA5,0xAA,0xBB,0xBC,0xBD,0xBC,0xAF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xFF}

#elif _CODE_PAGE == 1251 /* Cyrillic (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x82,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x80,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x8A,0x9B,0x8C,0x8D,0x8E,0x8F, \
        0xA0,0xA2,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB2,0xA5,0xB5,0xB6,0xB7,0xA8,0xB9,0xAA,0xBB,0xA3,0xBD,0xBD,0xAF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF}

#elif _CODE_PAGE == 1252 /* Latin 1 (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0xAd,0x9B,0x8C,0x9D,0xAE,0x9F, \
        0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0x9F}

#elif _CODE_PAGE == 1253 /* Greek (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xA2,0xB8,0xB9,0xBA, \
        0xE0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xF2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xFB,0xBC,0xFD,0xBF,0xFF}

#elif _CODE_PAGE == 1254 /* Turkish (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x8A,0x9B,0x8C,0x9D,0x9E,0x9F, \
        0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0x9F}

#elif _CODE_PAGE == 1255 /* Hebrew (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xE0,0xE1,0xE2,0xE3,0xE4,0xE5,0xE6,0xE7,0xE8,0xE9,0xEA,0xEB,0xEC,0xED,0xEE,0xEF,0xF0,0xF1,0xF2,0xF3,0xF4,0xF5,0xF6,0xF7,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 1256 /* Arabic (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x8C,0x9D,0x9E,0x9F, \
        0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0x41,0xE1,0x41,0xE3,0xE4,0xE5,0xE6,0x43,0x45,0x45,0x45,0x45,0xEC,0xED,0x49,0x49,0xF0,0xF1,0xF2,0xF3,0x4F,0xF5,0xF6,0xF7,0xF8,0x55,0xFA,0x55,0x55,0xFD,0xFE,0xFF}

#elif _CODE_PAGE == 1257 /* Baltic (Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0x9C,0x9D,0x9E,0x9F, \
        0xA0,0xA1,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xA8,0xB9,0xAA,0xBB,0xBC,0xBD,0xBE,0xAF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xFF}

#elif _CODE_PAGE == 1258 /* Vietnam (OEM, Windows) */
#define _DF1S 0
#define _EXCVT {0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87,0x88,0x89,0x8A,0x8B,0x8C,0x8D,0x8E,0x8F,0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97,0x98,0x99,0x9A,0x9B,0xAC,0x9D,0x9E,0x9F, \
        0xA0,0x21,0xA2,0xA3,0xA4,0xA5,0xA6,0xA7,0xA8,0xA9,0xAA,0xAB,0xAC,0xAD,0xAE,0xAF,0xB0,0xB1,0xB2,0xB3,0xB4,0xB5,0xB6,0xB7,0xB8,0xB9,0xBA,0xBB,0xBC,0xBD,0xBE,0xBF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xCC,0xCD,0xCE,0xCF,0xD0,0xD1,0xD2,0xD3,0xD4,0xD5,0xD6,0xD7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,0xDF, \
        0xC0,0xC1,0xC2,0xC3,0xC4,0xC5,0xC6,0xC7,0xC8,0xC9,0xCA,0xCB,0xEC,0xCD,0xCE,0xCF,0xD0,0xD1,0xF2,0xD3,0xD4,0xD5,0xD6,0xF7,0xD8,0xD9,0xDA,0xDB,0xDC,0xDD,0xFE,0x9F}

#elif _CODE_PAGE == 1 /* ASCII (for only non-LFN cfg) */
#if _USE_LFN
#error Cannot use LFN feature without valid code page.
#endif
#define _DF1S 0

#else
#error Unknown code page

#endif


/* Character code support macros */
#define IsUpper(c)  (((c)>='A')&&((c)<='Z'))
#define IsLower(c)  (((c)>='a')&&((c)<='z'))
#define IsDigit(c)  (((c)>='0')&&((c)<='9'))

#if _DF1S   /* Code page is DBCS */

#ifdef _DF2S  /* Two 1st byte areas */
#define IsDBCS1(c)  (((BYTE)(c) >= _DF1S && (BYTE)(c) <= _DF1E) || ((BYTE)(c) >= _DF2S && (BYTE)(c) <= _DF2E))
#else     /* One 1st byte area */
#define IsDBCS1(c)  ((BYTE)(c) >= _DF1S && (BYTE)(c) <= _DF1E)
#endif

#ifdef _DS3S  /* Three 2nd byte areas */
#define IsDBCS2(c)  (((BYTE)(c) >= _DS1S && (BYTE)(c) <= _DS1E) || ((BYTE)(c) >= _DS2S && (BYTE)(c) <= _DS2E) || ((BYTE)(c) >= _DS3S && (BYTE)(c) <= _DS3E))
#else     /* Two 2nd byte areas */
#define IsDBCS2(c)  (((BYTE)(c) >= _DS1S && (BYTE)(c) <= _DS1E) || ((BYTE)(c) >= _DS2S && (BYTE)(c) <= _DS2E))
#endif

#else     /* Code page is SBCS */

#define IsDBCS1(c)  0
#define IsDBCS2(c)  0

#endif /* _DF1S */


/* Name status flags */
#define NS      11    /* Index of name status byte in fn[] */
#define NS_LOSS   0x01  /* Out of 8.3 format */
#define NS_LFN    0x02  /* Force to create LFN entry */
#define NS_LAST   0x04  /* Last segment */
#define NS_BODY   0x08  /* Lower case flag (body) */
#define NS_EXT    0x10  /* Lower case flag (ext) */
#define NS_DOT    0x20  /* Dot entry */


/* FAT sub-type boundaries */
/* Note that the FAT spec by Microsoft says 4085 but Windows works with 4087! */
#define MIN_FAT16 4086  /* Minimum number of clusters for FAT16 */
#define MIN_FAT32 65526 /* Minimum number of clusters for FAT32 */


/* FatFs refers the members in the FAT structures as byte array instead of
/ structure member because the structure is not binary compatible between
/ different platforms */

#define BS_jmpBoot      0 /* Jump instruction (3) */
#define BS_OEMName      3 /* OEM name (8) */
#define BPB_BytsPerSec    11  /* Sector size [byte] (2) */
#define BPB_SecPerClus    13  /* Cluster size [sector] (1) */
#define BPB_RsvdSecCnt    14  /* Size of reserved area [sector] (2) */
#define BPB_NumFATs     16  /* Number of FAT copies (1) */
#define BPB_RootEntCnt    17  /* Number of root dir entries for FAT12/16 (2) */
#define BPB_TotSec16    19  /* Volume size [sector] (2) */
#define BPB_Media     21  /* Media descriptor (1) */
#define BPB_FATSz16     22  /* FAT size [sector] (2) */
#define BPB_SecPerTrk   24  /* Track size [sector] (2) */
#define BPB_NumHeads    26  /* Number of heads (2) */
#define BPB_HiddSec     28  /* Number of special hidden sectors (4) */
#define BPB_TotSec32    32  /* Volume size [sector] (4) */
#define BS_DrvNum     36  /* Physical drive number (2) */
#define BS_BootSig      38  /* Extended boot signature (1) */
#define BS_VolID      39  /* Volume serial number (4) */
#define BS_VolLab     43  /* Volume label (8) */
#define BS_FilSysType   54  /* File system type (1) */
#define BPB_FATSz32     36  /* FAT size [sector] (4) */
#define BPB_ExtFlags    40  /* Extended flags (2) */
#define BPB_FSVer     42  /* File system version (2) */
#define BPB_RootClus    44  /* Root dir first cluster (4) */
#define BPB_FSInfo      48  /* Offset of FSInfo sector (2) */
#define BPB_BkBootSec   50  /* Offset of backup boot sectot (2) */
#define BS_DrvNum32     64  /* Physical drive number (2) */
#define BS_BootSig32    66  /* Extended boot signature (1) */
#define BS_VolID32      67  /* Volume serial number (4) */
#define BS_VolLab32     71  /* Volume label (8) */
#define BS_FilSysType32   82  /* File system type (1) */
#define FSI_LeadSig     0 /* FSI: Leading signature (4) */
#define FSI_StrucSig    484 /* FSI: Structure signature (4) */
#define FSI_Free_Count    488 /* FSI: Number of free clusters (4) */
#define FSI_Nxt_Free    492 /* FSI: Last allocated cluster (4) */
#define MBR_Table     446 /* MBR: Partition table offset (2) */
#define SZ_PTE        16  /* MBR: Size of a partition table entry */
#define BS_55AA       510 /* Boot sector signature (2) */

#define DIR_Name      0 /* Short file name (11) */
#define DIR_Attr      11  /* Attribute (1) */
#define DIR_NTres     12  /* NT flag (1) */
#define DIR_CrtTime     14  /* Created time (2) */
#define DIR_CrtDate     16  /* Created date (2) */
#define DIR_FstClusHI   20  /* Higher 16-bit of first cluster (2) */
#define DIR_WrtTime     22  /* Modified time (2) */
#define DIR_WrtDate     24  /* Modified date (2) */
#define DIR_FstClusLO   26  /* Lower 16-bit of first cluster (2) */
#define DIR_FileSize    28  /* File size (4) */
#define LDIR_Ord      0 /* LFN entry order and LLE flag (1) */
#define LDIR_Attr     11  /* LFN attribute (1) */
#define LDIR_Type     12  /* LFN type (1) */
#define LDIR_Chksum     13  /* Sum of corresponding SFN entry */
#define LDIR_FstClusLO    26  /* Filled by zero (0) */
#define SZ_DIR        32    /* Size of a directory entry */
#define LLE         0x40  /* Last long entry flag in LDIR_Ord */
#define DDE         0xE5  /* Deleted directory enrty mark in DIR_Name[0] */
#define NDDE        0x05  /* Replacement of a character collides with DDE */


/*------------------------------------------------------------*/
/* Module private work area                                   */
/*------------------------------------------------------------*/
/* Note that uninitialized variables with static duration are
/  zeroed/nulled at start-up. If not, the compiler or start-up
/  routine is out of ANSI-C standard.
*/

#if _VOLUMES
static
FATFS *FatFs[_VOLUMES]; /* Pointer to the file system objects (logical drives) */
#else
#error Number of volumes must not be 0.
#endif

static
WORD Fsid;        /* File system mount ID */

#if _FS_RPATH
static
BYTE CurrVol;     /* Current drive */
#endif

#if _FS_SHARE
static
FILESEM Files[_FS_SHARE]; /* File lock semaphores */
#endif

#if _USE_LFN == 0     /* No LFN feature */
#define DEF_NAMEBUF     BYTE sfn[12]
#define INIT_BUF(dobj)    (dobj).fn = sfn
#define FREE_BUF()

#elif _USE_LFN == 1     /* LFN feature with static working buffer */
static WCHAR LfnBuf[_MAX_LFN+1];
#define DEF_NAMEBUF     BYTE sfn[12]
#define INIT_BUF(dobj)    { (dobj).fn = sfn; (dobj).lfn = LfnBuf; }
#define FREE_BUF()

#elif _USE_LFN == 2     /* LFN feature with dynamic working buffer on the stack */
#define DEF_NAMEBUF     BYTE sfn[12]; WCHAR lbuf[_MAX_LFN+1]
#define INIT_BUF(dobj)    { (dobj).fn = sfn; (dobj).lfn = lbuf; }
#define FREE_BUF()

#elif _USE_LFN == 3     /* LFN feature with dynamic working buffer on the heap */
#define DEF_NAMEBUF     BYTE sfn[12]; WCHAR *lfn
#define INIT_BUF(dobj)    { lfn = ff_memalloc((_MAX_LFN + 1) * 2); \
                if (!lfn) LEAVE_FF((dobj).fs, FR_NOT_ENOUGH_CORE); \
                (dobj).lfn = lfn; (dobj).fn = sfn; }
#define FREE_BUF()      ff_memfree(lfn)

#else
#error Wrong LFN configuration.
#endif




/*--------------------------------------------------------------------------

   Module Private Functions

---------------------------------------------------------------------------*/


/*-----------------------------------------------------------------------*/
/* String functions                                                      */
/*-----------------------------------------------------------------------*/

/* Copy memory to memory */
static
void mem_cpy (void* dst, const void* src, UINT cnt) {
  BYTE *d = (BYTE*)dst;
  const BYTE *s = (const BYTE*)src;

#if _WORD_ACCESS == 1
  while (cnt >= sizeof(int)) {
    *(int*)d = *(int*)s;
    d += sizeof(int); s += sizeof(int);
    cnt -= sizeof(int);
  }
#endif
  while (cnt--)
    *d++ = *s++;
}

/* Fill memory */
static
void mem_set (void* dst, int val, UINT cnt) {
  BYTE *d = (BYTE*)dst;

  while (cnt--)
    *d++ = (BYTE)val;
}

/* Compare memory to memory */
static
int mem_cmp (const void* dst, const void* src, UINT cnt) {
  const BYTE *d = (const BYTE *)dst, *s = (const BYTE *)src;
  int r = 0;

  while (cnt-- && (r = *d++ - *s++) == 0) ;
  return r;
}

/* Check if chr is contained in the string */
static
int chk_chr (const char* str, int chr) {
  while (*str && *str != chr) str++;
  return *str;
}



/*-----------------------------------------------------------------------*/
/* Request/Release grant to access the volume                            */
/*-----------------------------------------------------------------------*/
#if _FS_REENTRANT

static
int lock_fs (
  FATFS *fs   /* File system object */
)
{
  return ff_req_grant(fs->sobj);
}


static
void unlock_fs (
  FATFS *fs,    /* File system object */
  FRESULT res   /* Result code to be returned */
)
{
  if (res != FR_NOT_ENABLED &&
    res != FR_INVALID_DRIVE &&
    res != FR_INVALID_OBJECT &&
    res != FR_TIMEOUT) {
    ff_rel_grant(fs->sobj);
  }
}
#endif



/*-----------------------------------------------------------------------*/
/* File shareing control functions                                       */
/*-----------------------------------------------------------------------*/
#if _FS_SHARE

static
FRESULT chk_lock (  /* Check if the file can be accessed */
  DIR* dj,    /* Directory object pointing the file to be checked */
  int acc     /* Desired access (0:Read, 1:Write, 2:Delete/Rename) */
)
{
  UINT i, be;

  /* Search file semaphore table */
  for (i = be = 0; i < _FS_SHARE; i++) {
    if (Files[i].fs) {  /* Existing entry */
      if (Files[i].fs == dj->fs &&    /* Check if the file matched with an open file */
        Files[i].clu == dj->sclust &&
        Files[i].idx == dj->index) break;
    } else {      /* Blank entry */
      be++;
    }
  }
  if (i == _FS_SHARE) /* The file is not opened */
    return (be || acc == 2) ? FR_OK : FR_TOO_MANY_OPEN_FILES; /* Is there a blank entry for new file? */

  /* The file has been opened. Reject any open against writing file and all write mode open */
  return (acc || Files[i].ctr == 0x100) ? FR_LOCKED : FR_OK;
}


static
int enq_lock (void) /* Check if an entry is available for a new file */
{
  UINT i;

  for (i = 0; i < _FS_SHARE && Files[i].fs; i++) ;
  return (i == _FS_SHARE) ? 0 : 1;
}


static
UINT inc_lock ( /* Increment file open counter and returns its index (0:int error) */
  DIR* dj,  /* Directory object pointing the file to register or increment */
  int acc   /* Desired access mode (0:Read, !0:Write) */
)
{
  UINT i;


  for (i = 0; i < _FS_SHARE; i++) { /* Find the file */
    if (Files[i].fs == dj->fs &&
      Files[i].clu == dj->sclust &&
      Files[i].idx == dj->index) break;
  }

  if (i == _FS_SHARE) {       /* Not opened. Register it as new. */
    for (i = 0; i < _FS_SHARE && Files[i].fs; i++) ;
    if (i == _FS_SHARE) return 0; /* No space to register (int err) */
    Files[i].fs = dj->fs;
    Files[i].clu = dj->sclust;
    Files[i].idx = dj->index;
    Files[i].ctr = 0;
  }

  if (acc && Files[i].ctr) return 0;  /* Access violation (int err) */

  Files[i].ctr = acc ? 0x100 : Files[i].ctr + 1;  /* Set semaphore value */

  return i + 1;
}


static
FRESULT dec_lock (  /* Decrement file open counter */
  UINT i      /* Semaphore index */
)
{
  WORD n;
  FRESULT res;


  if (--i < _FS_SHARE) {
    n = Files[i].ctr;
    if (n == 0x100) n = 0;
    if (n) n--;
    Files[i].ctr = n;
    if (!n) Files[i].fs = 0;
    res = FR_OK;
  } else {
    res = FR_INT_ERR;
  }
  return res;
}


static
void clear_lock ( /* Clear lock entries of the volume */
  FATFS *fs
)
{
  UINT i;

  for (i = 0; i < _FS_SHARE; i++) {
    if (Files[i].fs == fs) Files[i].fs = 0;
  }
}
#endif



/*-----------------------------------------------------------------------*/
/* Change window offset                                                  */
/*-----------------------------------------------------------------------*/

static
FRESULT move_window (
  FATFS *fs,    /* File system object */
  DWORD sector  /* Sector number to make appearance in the fs->win[] */
)         /* Move to zero only writes back dirty window */
{
  DWORD wsect;


  wsect = fs->winsect;
  if (wsect != sector) {  /* Changed current window */
#if !_FS_READONLY
    if (fs->wflag) {  /* Write back dirty window if needed */
      if (disk_write(fs->drv, fs->win, wsect, 1) != RES_OK)
        return FR_DISK_ERR;
      fs->wflag = 0;
      if (wsect < (fs->fatbase + fs->fsize)) {  /* In FAT area */
        BYTE nf;
        for (nf = fs->n_fats; nf > 1; nf--) { /* Reflect the change to all FAT copies */
          wsect += fs->fsize;
          disk_write(fs->drv, fs->win, wsect, 1);
        }
      }
    }
#endif
    if (sector) {
      if (disk_read(fs->drv, fs->win, sector, 1) != RES_OK)
        return FR_DISK_ERR;
      fs->winsect = sector;
    }
  }

  return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Clean-up cached data                                                  */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
FRESULT sync (  /* FR_OK: successful, FR_DISK_ERR: failed */
  FATFS *fs /* File system object */
)
{
  FRESULT res;


  res = move_window(fs, 0);
  if (res == FR_OK) {
    /* Update FSInfo sector if needed */
    if (fs->fs_type == FS_FAT32 && fs->fsi_flag) {
      fs->winsect = 0;
      /* Create FSInfo structure */
      mem_set(fs->win, 0, 512);
      ST_WORD(fs->win+BS_55AA, 0xAA55);
      ST_DWORD(fs->win+FSI_LeadSig, 0x41615252);
      ST_DWORD(fs->win+FSI_StrucSig, 0x61417272);
      ST_DWORD(fs->win+FSI_Free_Count, fs->free_clust);
      ST_DWORD(fs->win+FSI_Nxt_Free, fs->last_clust);
      /* Write it into the FSInfo sector */
      disk_write(fs->drv, fs->win, fs->fsi_sector, 1);
      fs->fsi_flag = 0;
    }
    /* Make sure that no pending write process in the physical drive */
    if (disk_ioctl(fs->drv, CTRL_SYNC, 0) != RES_OK)
      res = FR_DISK_ERR;
  }

  return res;
}
#endif




/*-----------------------------------------------------------------------*/
/* Get sector# from cluster#                                             */
/*-----------------------------------------------------------------------*/


DWORD clust2sect (  /* !=0: Sector number, 0: Failed - invalid cluster# */
  FATFS *fs,    /* File system object */
  DWORD clst    /* Cluster# to be converted */
)
{
  clst -= 2;
  if (clst >= (fs->n_fatent - 2)) return 0;   /* Invalid cluster# */
  return clst * fs->csize + fs->database;
}




/*-----------------------------------------------------------------------*/
/* FAT access - Read value of a FAT entry                                */
/*-----------------------------------------------------------------------*/


DWORD get_fat ( /* 0xFFFFFFFF:Disk error, 1:Internal error, Else:Cluster status */
  FATFS *fs,  /* File system object */
  DWORD clst  /* Cluster# to get the link information */
)
{
  UINT wc, bc;
  BYTE *p;


  if (clst < 2 || clst >= fs->n_fatent) /* Chack range */
    return 1;

  switch (fs->fs_type) {
  case FS_FAT12 :
    bc = (UINT)clst; bc += bc / 2;
    if (move_window(fs, fs->fatbase + (bc / SS(fs)))) break;
    wc = fs->win[bc % SS(fs)]; bc++;
    if (move_window(fs, fs->fatbase + (bc / SS(fs)))) break;
    wc |= fs->win[bc % SS(fs)] << 8;
    return (clst & 1) ? (wc >> 4) : (wc & 0xFFF);

  case FS_FAT16 :
    if (move_window(fs, fs->fatbase + (clst / (SS(fs) / 2)))) break;
    p = &fs->win[clst * 2 % SS(fs)];
    return LD_WORD(p);

  case FS_FAT32 :
    if (move_window(fs, fs->fatbase + (clst / (SS(fs) / 4)))) break;
    p = &fs->win[clst * 4 % SS(fs)];
    return LD_DWORD(p) & 0x0FFFFFFF;
  }

  return 0xFFFFFFFF;  /* An error occurred at the disk I/O layer */
}




/*-----------------------------------------------------------------------*/
/* FAT access - Change value of a FAT entry                              */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY

FRESULT put_fat (
  FATFS *fs,  /* File system object */
  DWORD clst, /* Cluster# to be changed in range of 2 to fs->n_fatent - 1 */
  DWORD val /* New value to mark the cluster */
)
{
  UINT bc;
  BYTE *p;
  FRESULT res;


  if (clst < 2 || clst >= fs->n_fatent) { /* Check range */
    res = FR_INT_ERR;

  } else {
    switch (fs->fs_type) {
    case FS_FAT12 :
      bc = clst; bc += bc / 2;
      res = move_window(fs, fs->fatbase + (bc / SS(fs)));
      if (res != FR_OK) break;
      p = &fs->win[bc % SS(fs)];
      *p = (clst & 1) ? ((*p & 0x0F) | ((BYTE)val << 4)) : (BYTE)val;
      bc++;
      fs->wflag = 1;
      res = move_window(fs, fs->fatbase + (bc / SS(fs)));
      if (res != FR_OK) break;
      p = &fs->win[bc % SS(fs)];
      *p = (clst & 1) ? (BYTE)(val >> 4) : ((*p & 0xF0) | ((BYTE)(val >> 8) & 0x0F));
      break;

    case FS_FAT16 :
      res = move_window(fs, fs->fatbase + (clst / (SS(fs) / 2)));
      if (res != FR_OK) break;
      p = &fs->win[clst * 2 % SS(fs)];
      ST_WORD(p, (WORD)val);
      break;

    case FS_FAT32 :
      res = move_window(fs, fs->fatbase + (clst / (SS(fs) / 4)));
      if (res != FR_OK) break;
      p = &fs->win[clst * 4 % SS(fs)];
      val |= LD_DWORD(p) & 0xF0000000;
      ST_DWORD(p, val);
      break;

    default :
      res = FR_INT_ERR;
    }
    fs->wflag = 1;
  }

  return res;
}
#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* FAT handling - Remove a cluster chain                                 */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
FRESULT remove_chain (
  FATFS *fs,      /* File system object */
  DWORD clst      /* Cluster# to remove a chain from */
)
{
  FRESULT res;
  DWORD nxt;
#if _USE_ERASE
  DWORD scl = clst, ecl = clst, resion[2];
#endif

  if (clst < 2 || clst >= fs->n_fatent) { /* Check range */
    res = FR_INT_ERR;

  } else {
    res = FR_OK;
    while (clst < fs->n_fatent) {     /* Not a last link? */
      nxt = get_fat(fs, clst);      /* Get cluster status */
      if (nxt == 0) break;        /* Empty cluster? */
      if (nxt == 1) { res = FR_INT_ERR; break; }  /* Internal error? */
      if (nxt == 0xFFFFFFFF) { res = FR_DISK_ERR; break; }  /* Disk error? */
      res = put_fat(fs, clst, 0);     /* Mark the cluster "empty" */
      if (res != FR_OK) break;
      if (fs->free_clust != 0xFFFFFFFF) { /* Update FSInfo */
        fs->free_clust++;
        fs->fsi_flag = 1;
      }
#if _USE_ERASE
      if (ecl + 1 == nxt) { /* Next cluster is contiguous */
        ecl = nxt;
      } else {        /* End of contiguous clusters */
        resion[0] = clust2sect(fs, scl);          /* Start sector */
        resion[1] = clust2sect(fs, ecl) + fs->csize - 1;  /* End sector */
        disk_ioctl(fs->drv, CTRL_ERASE_SECTOR, resion);   /* Erase the block */
        scl = ecl = nxt;
      }
#endif
      clst = nxt; /* Next cluster */
    }
  }

  return res;
}
#endif




/*-----------------------------------------------------------------------*/
/* FAT handling - Stretch or Create a cluster chain                      */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
DWORD create_chain (  /* 0:No free cluster, 1:Internal error, 0xFFFFFFFF:Disk error, >=2:New cluster# */
  FATFS *fs,      /* File system object */
  DWORD clst      /* Cluster# to stretch. 0 means create a new chain. */
)
{
  DWORD cs, ncl, scl;
  FRESULT res;


  if (clst == 0) {    /* Create a new chain */
    scl = fs->last_clust;     /* Get suggested start point */
    if (!scl || scl >= fs->n_fatent) scl = 1;
  }
  else {          /* Stretch the current chain */
    cs = get_fat(fs, clst);     /* Check the cluster status */
    if (cs < 2) return 1;     /* It is an invalid cluster */
    if (cs < fs->n_fatent) return cs; /* It is already followed by next cluster */
    scl = clst;
  }

  ncl = scl;        /* Start cluster */
  for (;;) {
    ncl++;              /* Next cluster */
    if (ncl >= fs->n_fatent) {    /* Wrap around */
      ncl = 2;
      if (ncl > scl) return 0;  /* No free cluster */
    }
    cs = get_fat(fs, ncl);      /* Get the cluster status */
    if (cs == 0) break;       /* Found a free cluster */
    if (cs == 0xFFFFFFFF || cs == 1)/* An error occurred */
      return cs;
    if (ncl == scl) return 0;   /* No free cluster */
  }

  res = put_fat(fs, ncl, 0x0FFFFFFF); /* Mark the new cluster "last link" */
  if (res == FR_OK && clst != 0) {
    res = put_fat(fs, clst, ncl); /* Link it to the previous one if needed */
  }
  if (res == FR_OK) {
    fs->last_clust = ncl;     /* Update FSINFO */
    if (fs->free_clust != 0xFFFFFFFF) {
      fs->free_clust--;
      fs->fsi_flag = 1;
    }
  } else {
    ncl = (res == FR_DISK_ERR) ? 0xFFFFFFFF : 1;
  }

  return ncl;   /* Return new cluster number or error code */
}
#endif /* !_FS_READONLY */



/*-----------------------------------------------------------------------*/
/* FAT handling - Convert offset into cluster with link map table        */
/*-----------------------------------------------------------------------*/

#if _USE_FASTSEEK
static
DWORD clmt_clust (  /* <2:Error, >=2:Cluster number */
  FIL* fp,    /* Pointer to the file object */
  DWORD ofs   /* File offset to be converted to cluster# */
)
{
  DWORD cl, ncl, *tbl;


  tbl = fp->cltbl + 1;  /* Top of CLMT */
  cl = ofs / SS(fp->fs) / fp->fs->csize;  /* Cluster order from top of the file */
  for (;;) {
    ncl = *tbl++;     /* Number of cluters in the fragment */
    if (!ncl) return 0;   /* End of table? (error) */
    if (cl < ncl) break;  /* In this fragment? */
    cl -= ncl; tbl++;   /* Next fragment */
  }
  return cl + *tbl; /* Return the cluster number */
}
#endif  /* _USE_FASTSEEK */



/*-----------------------------------------------------------------------*/
/* Directory handling - Set directory index                              */
/*-----------------------------------------------------------------------*/

static
FRESULT dir_sdi (
  DIR *dj,    /* Pointer to directory object */
  WORD idx    /* Directory index number */
)
{
  DWORD clst;
  WORD ic;


  dj->index = idx;
  clst = dj->sclust;
  if (clst == 1 || clst >= dj->fs->n_fatent)  /* Check start cluster range */
    return FR_INT_ERR;
  if (!clst && dj->fs->fs_type == FS_FAT32) /* Replace cluster# 0 with root cluster# if in FAT32 */
    clst = dj->fs->dirbase;

  if (clst == 0) {  /* Static table (root-dir in FAT12/16) */
    dj->clust = clst;
    if (idx >= dj->fs->n_rootdir)   /* Index is out of range */
      return FR_INT_ERR;
    dj->sect = dj->fs->dirbase + idx / (SS(dj->fs) / SZ_DIR); /* Sector# */
  }
  else {        /* Dynamic table (sub-dirs or root-dir in FAT32) */
    ic = SS(dj->fs) / SZ_DIR * dj->fs->csize; /* Entries per cluster */
    while (idx >= ic) { /* Follow cluster chain */
      clst = get_fat(dj->fs, clst);       /* Get next cluster */
      if (clst == 0xFFFFFFFF) return FR_DISK_ERR; /* Disk error */
      if (clst < 2 || clst >= dj->fs->n_fatent) /* Reached to end of table or int error */
        return FR_INT_ERR;
      idx -= ic;
    }
    dj->clust = clst;
    dj->sect = clust2sect(dj->fs, clst) + idx / (SS(dj->fs) / SZ_DIR);  /* Sector# */
  }

  dj->dir = dj->fs->win + (idx % (SS(dj->fs) / SZ_DIR)) * SZ_DIR; /* Ptr to the entry in the sector */

  return FR_OK; /* Seek succeeded */
}




/*-----------------------------------------------------------------------*/
/* Directory handling - Move directory index next                        */
/*-----------------------------------------------------------------------*/

static
FRESULT dir_next (  /* FR_OK:Succeeded, FR_NO_FILE:End of table, FR_DENIED:EOT and could not stretch */
  DIR *dj,    /* Pointer to directory object */
  int stretch   /* 0: Do not stretch table, 1: Stretch table if needed */
)
{
  DWORD clst;
  WORD i;


  stretch = stretch;    /* To suppress warning on read-only cfg. */
  i = dj->index + 1;
  if (!i || !dj->sect)  /* Report EOT when index has reached 65535 */
    return FR_NO_FILE;

  if (!(i % (SS(dj->fs) / SZ_DIR))) { /* Sector changed? */
    dj->sect++;         /* Next sector */

    if (dj->clust == 0) { /* Static table */
      if (i >= dj->fs->n_rootdir) /* Report EOT when end of table */
        return FR_NO_FILE;
    }
    else {          /* Dynamic table */
      if (((i / (SS(dj->fs) / SZ_DIR)) & (dj->fs->csize - 1)) == 0) { /* Cluster changed? */
        clst = get_fat(dj->fs, dj->clust);        /* Get next cluster */
        if (clst <= 1) return FR_INT_ERR;
        if (clst == 0xFFFFFFFF) return FR_DISK_ERR;
        if (clst >= dj->fs->n_fatent) {         /* When it reached end of dynamic table */
#if !_FS_READONLY
          BYTE c;
          if (!stretch) return FR_NO_FILE;      /* When do not stretch, report EOT */
          clst = create_chain(dj->fs, dj->clust);   /* Stretch cluster chain */
          if (clst == 0) return FR_DENIED;      /* No free cluster */
          if (clst == 1) return FR_INT_ERR;
          if (clst == 0xFFFFFFFF) return FR_DISK_ERR;
          /* Clean-up stretched table */
          if (move_window(dj->fs, 0)) return FR_DISK_ERR; /* Flush active window */
          mem_set(dj->fs->win, 0, SS(dj->fs));      /* Clear window buffer */
          dj->fs->winsect = clust2sect(dj->fs, clst); /* Cluster start sector */
          for (c = 0; c < dj->fs->csize; c++) {   /* Fill the new cluster with 0 */
            dj->fs->wflag = 1;
            if (move_window(dj->fs, 0)) return FR_DISK_ERR;
            dj->fs->winsect++;
          }
          dj->fs->winsect -= c;           /* Rewind window address */
#else
          return FR_NO_FILE;      /* Report EOT */
#endif
        }
        dj->clust = clst;       /* Initialize data for new cluster */
        dj->sect = clust2sect(dj->fs, clst);
      }
    }
  }

  dj->index = i;
  dj->dir = dj->fs->win + (i % (SS(dj->fs) / SZ_DIR)) * SZ_DIR;

  return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* LFN handling - Test/Pick/Fit an LFN segment from/to directory entry   */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
static
const BYTE LfnOfs[] = {1,3,5,7,9,14,16,18,20,22,24,28,30};  /* Offset of LFN chars in the directory entry */


static
int cmp_lfn (     /* 1:Matched, 0:Not matched */
  WCHAR *lfnbuf,    /* Pointer to the LFN to be compared */
  BYTE *dir     /* Pointer to the directory entry containing a part of LFN */
)
{
  UINT i, s;
  WCHAR wc, uc;


  i = ((dir[LDIR_Ord] & ~LLE) - 1) * 13;  /* Get offset in the LFN buffer */
  s = 0; wc = 1;
  do {
    uc = LD_WORD(dir+LfnOfs[s]);  /* Pick an LFN character from the entry */
    if (wc) { /* Last char has not been processed */
      wc = ff_wtoupper(uc);   /* Convert it to upper case */
      if (i >= _MAX_LFN || wc != ff_wtoupper(lfnbuf[i++]))  /* Compare it */
        return 0;       /* Not matched */
    } else {
      if (uc != 0xFFFF) return 0; /* Check filler */
    }
  } while (++s < 13);       /* Repeat until all chars in the entry are checked */

  if ((dir[LDIR_Ord] & LLE) && wc && lfnbuf[i]) /* Last segment matched but different length */
    return 0;

  return 1;           /* The part of LFN matched */
}



static
int pick_lfn (      /* 1:Succeeded, 0:Buffer overflow */
  WCHAR *lfnbuf,    /* Pointer to the Unicode-LFN buffer */
  BYTE *dir     /* Pointer to the directory entry */
)
{
  UINT i, s;
  WCHAR wc, uc;


  i = ((dir[LDIR_Ord] & 0x3F) - 1) * 13;  /* Offset in the LFN buffer */

  s = 0; wc = 1;
  do {
    uc = LD_WORD(dir+LfnOfs[s]);    /* Pick an LFN character from the entry */
    if (wc) { /* Last char has not been processed */
      if (i >= _MAX_LFN) return 0;  /* Buffer overflow? */
      lfnbuf[i++] = wc = uc;      /* Store it */
    } else {
      if (uc != 0xFFFF) return 0;   /* Check filler */
    }
  } while (++s < 13);           /* Read all character in the entry */

  if (dir[LDIR_Ord] & LLE) {        /* Put terminator if it is the last LFN part */
    if (i >= _MAX_LFN) return 0;    /* Buffer overflow? */
    lfnbuf[i] = 0;
  }

  return 1;
}


#if !_FS_READONLY
static
void fit_lfn (
  const WCHAR *lfnbuf,  /* Pointer to the LFN buffer */
  BYTE *dir,        /* Pointer to the directory entry */
  BYTE ord,       /* LFN order (1-20) */
  BYTE sum        /* SFN sum */
)
{
  UINT i, s;
  WCHAR wc;


  dir[LDIR_Chksum] = sum;     /* Set check sum */
  dir[LDIR_Attr] = AM_LFN;    /* Set attribute. LFN entry */
  dir[LDIR_Type] = 0;
  ST_WORD(dir+LDIR_FstClusLO, 0);

  i = (ord - 1) * 13;       /* Get offset in the LFN buffer */
  s = wc = 0;
  do {
    if (wc != 0xFFFF) wc = lfnbuf[i++]; /* Get an effective char */
    ST_WORD(dir+LfnOfs[s], wc); /* Put it */
    if (!wc) wc = 0xFFFF;   /* Padding chars following last char */
  } while (++s < 13);
  if (wc == 0xFFFF || !lfnbuf[i]) ord |= LLE; /* Bottom LFN part is the start of LFN sequence */
  dir[LDIR_Ord] = ord;      /* Set the LFN order */
}

#endif
#endif



/*-----------------------------------------------------------------------*/
/* Create numbered name                                                  */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
void gen_numname (
  BYTE *dst,      /* Pointer to generated SFN */
  const BYTE *src,  /* Pointer to source SFN to be modified */
  const WCHAR *lfn, /* Pointer to LFN */
  WORD seq      /* Sequence number */
)
{
  BYTE ns[8], c;
  UINT i, j;


  mem_cpy(dst, src, 11);

  if (seq > 5) {  /* On many collisions, generate a hash number instead of sequential number */
    do seq = (seq >> 1) + (seq << 15) + (WORD)*lfn++; while (*lfn);
  }

  /* itoa (hexdecimal) */
  i = 7;
  do {
    c = (seq % 16) + '0';
    if (c > '9') c += 7;
    ns[i--] = c;
    seq /= 16;
  } while (seq);
  ns[i] = '~';

  /* Append the number */
  for (j = 0; j < i && dst[j] != ' '; j++) {
    if (IsDBCS1(dst[j])) {
      if (j == i - 1) break;
      j++;
    }
  }
  do {
    dst[j++] = (i < 8) ? ns[i++] : ' ';
  } while (j < 8);
}
#endif




/*-----------------------------------------------------------------------*/
/* Calculate sum of an SFN                                               */
/*-----------------------------------------------------------------------*/
#if _USE_LFN
static
BYTE sum_sfn (
  const BYTE *dir   /* Ptr to directory entry */
)
{
  BYTE sum = 0;
  UINT n = 11;

  do sum = (sum >> 1) + (sum << 7) + *dir++; while (--n);
  return sum;
}
#endif




/*-----------------------------------------------------------------------*/
/* Directory handling - Find an object in the directory                  */
/*-----------------------------------------------------------------------*/

static
FRESULT dir_find (
  DIR *dj     /* Pointer to the directory object linked to the file name */
)
{
  FRESULT res;
  BYTE c, *dir;
#if _USE_LFN
  BYTE a, ord, sum;
#endif

  res = dir_sdi(dj, 0);     /* Rewind directory object */
  if (res != FR_OK) return res;

#if _USE_LFN
  ord = sum = 0xFF;
#endif
  do {
    res = move_window(dj->fs, dj->sect);
    if (res != FR_OK) break;
    dir = dj->dir;          /* Ptr to the directory entry of current index */
    c = dir[DIR_Name];
    if (c == 0) { res = FR_NO_FILE; break; }  /* Reached to end of table */
#if _USE_LFN  /* LFN configuration */
    a = dir[DIR_Attr] & AM_MASK;
    if (c == DDE || ((a & AM_VOL) && a != AM_LFN)) {  /* An entry without valid data */
      ord = 0xFF;
    } else {
      if (a == AM_LFN) {      /* An LFN entry is found */
        if (dj->lfn) {
          if (c & LLE) {    /* Is it start of LFN sequence? */
            sum = dir[LDIR_Chksum];
            c &= ~LLE; ord = c; /* LFN start order */
            dj->lfn_idx = dj->index;
          }
          /* Check validity of the LFN entry and compare it with given name */
          ord = (c == ord && sum == dir[LDIR_Chksum] && cmp_lfn(dj->lfn, dir)) ? ord - 1 : 0xFF;
        }
      } else {          /* An SFN entry is found */
        if (!ord && sum == sum_sfn(dir)) break; /* LFN matched? */
        ord = 0xFF; dj->lfn_idx = 0xFFFF; /* Reset LFN sequence */
        if (!(dj->fn[NS] & NS_LOSS) && !mem_cmp(dir, dj->fn, 11)) break;  /* SFN matched? */
      }
    }
#else   /* Non LFN configuration */
    if (!(dir[DIR_Attr] & AM_VOL) && !mem_cmp(dir, dj->fn, 11)) /* Is it a valid entry? */
      break;
#endif
    res = dir_next(dj, 0);    /* Next entry */
  } while (res == FR_OK);

  return res;
}




/*-----------------------------------------------------------------------*/
/* Read an object from the directory                                     */
/*-----------------------------------------------------------------------*/
#if _FS_MINIMIZE <= 1
static
FRESULT dir_read (
  DIR *dj     /* Pointer to the directory object that pointing the entry to be read */
)
{
  FRESULT res;
  BYTE c, *dir;
#if _USE_LFN
  BYTE a, ord = 0xFF, sum = 0xFF;
#endif

  res = FR_NO_FILE;
  while (dj->sect) {
    res = move_window(dj->fs, dj->sect);
    if (res != FR_OK) break;
    dir = dj->dir;          /* Ptr to the directory entry of current index */
    c = dir[DIR_Name];
    if (c == 0) { res = FR_NO_FILE; break; }  /* Reached to end of table */
#if _USE_LFN  /* LFN configuration */
    a = dir[DIR_Attr] & AM_MASK;
    if (c == DDE || (!_FS_RPATH && c == '.') || ((a & AM_VOL) && a != AM_LFN)) {  /* An entry without valid data */
      ord = 0xFF;
    } else {
      if (a == AM_LFN) {      /* An LFN entry is found */
        if (c & LLE) {      /* Is it start of LFN sequence? */
          sum = dir[LDIR_Chksum];
          c &= ~LLE; ord = c;
          dj->lfn_idx = dj->index;
        }
        /* Check LFN validity and capture it */
        ord = (c == ord && sum == dir[LDIR_Chksum] && pick_lfn(dj->lfn, dir)) ? ord - 1 : 0xFF;
      } else {          /* An SFN entry is found */
        if (ord || sum != sum_sfn(dir)) /* Is there a valid LFN? */
          dj->lfn_idx = 0xFFFF;   /* It has no LFN. */
        break;
      }
    }
#else   /* Non LFN configuration */
    if (c != DDE && (_FS_RPATH || c != '.') && !(dir[DIR_Attr] & AM_VOL)) /* Is it a valid entry? */
      break;
#endif
    res = dir_next(dj, 0);        /* Next entry */
    if (res != FR_OK) break;
  }

  if (res != FR_OK) dj->sect = 0;

  return res;
}
#endif



/*-----------------------------------------------------------------------*/
/* Register an object to the directory                                   */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY
static
FRESULT dir_register (  /* FR_OK:Successful, FR_DENIED:No free entry or too many SFN collision, FR_DISK_ERR:Disk error */
  DIR *dj       /* Target directory with object name to be created */
)
{
  FRESULT res;
  BYTE c, *dir;
#if _USE_LFN  /* LFN configuration */
  WORD n, ne, is;
  BYTE sn[12], *fn, sum;
  WCHAR *lfn;


  fn = dj->fn; lfn = dj->lfn;
  mem_cpy(sn, fn, 12);

  if (_FS_RPATH && (sn[NS] & NS_DOT))   /* Cannot create dot entry */
    return FR_INVALID_NAME;

  if (sn[NS] & NS_LOSS) {     /* When LFN is out of 8.3 format, generate a numbered name */
    fn[NS] = 0; dj->lfn = 0;      /* Find only SFN */
    for (n = 1; n < 100; n++) {
      gen_numname(fn, sn, lfn, n);  /* Generate a numbered name */
      res = dir_find(dj);       /* Check if the name collides with existing SFN */
      if (res != FR_OK) break;
    }
    if (n == 100) return FR_DENIED;   /* Abort if too many collisions */
    if (res != FR_NO_FILE) return res;  /* Abort if the result is other than 'not collided' */
    fn[NS] = sn[NS]; dj->lfn = lfn;
  }

  if (sn[NS] & NS_LFN) {      /* When LFN is to be created, reserve an SFN + LFN entries. */
    for (ne = 0; lfn[ne]; ne++) ;
    ne = (ne + 25) / 13;
  } else {            /* Otherwise reserve only an SFN entry. */
    ne = 1;
  }

  /* Reserve contiguous entries */
  res = dir_sdi(dj, 0);
  if (res != FR_OK) return res;
  n = is = 0;
  do {
    res = move_window(dj->fs, dj->sect);
    if (res != FR_OK) break;
    c = *dj->dir;       /* Check the entry status */
    if (c == DDE || c == 0) { /* Is it a blank entry? */
      if (n == 0) is = dj->index; /* First index of the contiguous entry */
      if (++n == ne) break; /* A contiguous entry that required count is found */
    } else {
      n = 0;          /* Not a blank entry. Restart to search */
    }
    res = dir_next(dj, 1);    /* Next entry with table stretch */
  } while (res == FR_OK);

  if (res == FR_OK && ne > 1) { /* Initialize LFN entry if needed */
    res = dir_sdi(dj, is);
    if (res == FR_OK) {
      sum = sum_sfn(dj->fn);  /* Sum of the SFN tied to the LFN */
      ne--;
      do {          /* Store LFN entries in bottom first */
        res = move_window(dj->fs, dj->sect);
        if (res != FR_OK) break;
        fit_lfn(dj->lfn, dj->dir, (BYTE)ne, sum);
        dj->fs->wflag = 1;
        res = dir_next(dj, 0);  /* Next entry */
      } while (res == FR_OK && --ne);
    }
  }

#else /* Non LFN configuration */
  res = dir_sdi(dj, 0);
  if (res == FR_OK) {
    do {  /* Find a blank entry for the SFN */
      res = move_window(dj->fs, dj->sect);
      if (res != FR_OK) break;
      c = *dj->dir;
      if (c == DDE || c == 0) break;  /* Is it a blank entry? */
      res = dir_next(dj, 1);      /* Next entry with table stretch */
    } while (res == FR_OK);
  }
#endif

  if (res == FR_OK) {   /* Initialize the SFN entry */
    res = move_window(dj->fs, dj->sect);
    if (res == FR_OK) {
      dir = dj->dir;
      mem_set(dir, 0, SZ_DIR);  /* Clean the entry */
      mem_cpy(dir, dj->fn, 11); /* Put SFN */
#if _USE_LFN
      dir[DIR_NTres] = *(dj->fn+NS) & (NS_BODY | NS_EXT); /* Put NT flag */
#endif
      dj->fs->wflag = 1;
    }
  }

  return res;
}
#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* Remove an object from the directory                                   */
/*-----------------------------------------------------------------------*/
#if !_FS_READONLY && !_FS_MINIMIZE
static
FRESULT dir_remove (  /* FR_OK: Successful, FR_DISK_ERR: A disk error */
  DIR *dj       /* Directory object pointing the entry to be removed */
)
{
  FRESULT res;
#if _USE_LFN  /* LFN configuration */
  WORD i;

  i = dj->index;  /* SFN index */
  res = dir_sdi(dj, (WORD)((dj->lfn_idx == 0xFFFF) ? i : dj->lfn_idx)); /* Goto the SFN or top of the LFN entries */
  if (res == FR_OK) {
    do {
      res = move_window(dj->fs, dj->sect);
      if (res != FR_OK) break;
      *dj->dir = DDE;     /* Mark the entry "deleted" */
      dj->fs->wflag = 1;
      if (dj->index >= i) break;  /* When reached SFN, all entries of the object has been deleted. */
      res = dir_next(dj, 0);    /* Next entry */
    } while (res == FR_OK);
    if (res == FR_NO_FILE) res = FR_INT_ERR;
  }

#else     /* Non LFN configuration */
  res = dir_sdi(dj, dj->index);
  if (res == FR_OK) {
    res = move_window(dj->fs, dj->sect);
    if (res == FR_OK) {
      *dj->dir = DDE;     /* Mark the entry "deleted" */
      dj->fs->wflag = 1;
    }
  }
#endif

  return res;
}
#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* Pick a segment and create the object name in directory form           */
/*-----------------------------------------------------------------------*/

static
FRESULT create_name (
  DIR *dj,      /* Pointer to the directory object */
  const TCHAR **path  /* Pointer to pointer to the segment in the path string */
)
{
#ifdef _EXCVT
  static const BYTE excvt[] = _EXCVT; /* Upper conversion table for extended chars */
#endif

#if _USE_LFN  /* LFN configuration */
  BYTE b, cf;
  WCHAR w, *lfn;
  UINT i, ni, si, di;
  const TCHAR *p;

  /* Create LFN in Unicode */
  for (p = *path; *p == '/' || *p == '\\'; p++) ; /* Strip duplicated separator */
  lfn = dj->lfn;
  si = di = 0;
  for (;;) {
    w = p[si++];          /* Get a character */
    if (w < ' ' || w == '/' || w == '\\') break;  /* Break on end of segment */
    if (di >= _MAX_LFN)       /* Reject too long name */
      return FR_INVALID_NAME;
#if !_LFN_UNICODE
    w &= 0xFF;
    if (IsDBCS1(w)) {       /* Check if it is a DBC 1st byte (always false on SBCS cfg) */
      b = (BYTE)p[si++];      /* Get 2nd byte */
      if (!IsDBCS2(b))
        return FR_INVALID_NAME; /* Reject invalid sequence */
      w = (w << 8) + b;     /* Create a DBC */
    }
    w = ff_convert(w, 1);     /* Convert ANSI/OEM to Unicode */
    if (!w) return FR_INVALID_NAME; /* Reject invalid code */
#endif
    if (w < 0x80 && chk_chr("\"*:<>\?|\x7F", w)) /* Reject illegal chars for LFN */
      return FR_INVALID_NAME;
    lfn[di++] = w;          /* Store the Unicode char */
  }
  *path = &p[si];           /* Return pointer to the next segment */
  cf = (w < ' ') ? NS_LAST : 0;   /* Set last segment flag if end of path */
#if _FS_RPATH
  if ((di == 1 && lfn[di-1] == '.') || /* Is this a dot entry? */
    (di == 2 && lfn[di-1] == '.' && lfn[di-2] == '.')) {
    lfn[di] = 0;
    for (i = 0; i < 11; i++)
      dj->fn[i] = (i < di) ? '.' : ' ';
    dj->fn[i] = cf | NS_DOT;    /* This is a dot entry */
    return FR_OK;
  }
#endif
  while (di) {            /* Strip trailing spaces and dots */
    w = lfn[di-1];
    if (w != ' ' && w != '.') break;
    di--;
  }
  if (!di) return FR_INVALID_NAME;  /* Reject nul string */

  lfn[di] = 0;            /* LFN is created */

  /* Create SFN in directory form */
  mem_set(dj->fn, ' ', 11);
  for (si = 0; lfn[si] == ' ' || lfn[si] == '.'; si++) ;  /* Strip leading spaces and dots */
  if (si) cf |= NS_LOSS | NS_LFN;
  while (di && lfn[di - 1] != '.') di--;  /* Find extension (di<=si: no extension) */

  b = i = 0; ni = 8;
  for (;;) {
    w = lfn[si++];          /* Get an LFN char */
    if (!w) break;          /* Break on end of the LFN */
    if (w == ' ' || (w == '.' && si != di)) { /* Remove spaces and dots */
      cf |= NS_LOSS | NS_LFN; continue;
    }

    if (i >= ni || si == di) {    /* Extension or end of SFN */
      if (ni == 11) {       /* Long extension */
        cf |= NS_LOSS | NS_LFN; break;
      }
      if (si != di) cf |= NS_LOSS | NS_LFN; /* Out of 8.3 format */
      if (si > di) break;     /* No extension */
      si = di; i = 8; ni = 11;  /* Enter extension section */
      b <<= 2; continue;
    }

    if (w >= 0x80) {        /* Non ASCII char */
#ifdef _EXCVT
      w = ff_convert(w, 0);   /* Unicode -> OEM code */
      if (w) w = excvt[w - 0x80]; /* Convert extended char to upper (SBCS) */
#else
      w = ff_convert(ff_wtoupper(w), 0);  /* Upper converted Unicode -> OEM code */
#endif
      cf |= NS_LFN;       /* Force create LFN entry */
    }

    if (_DF1S && w >= 0x100) {    /* Double byte char (always false on SBCS cfg) */
      if (i >= ni - 1) {
        cf |= NS_LOSS | NS_LFN; i = ni; continue;
      }
      dj->fn[i++] = (BYTE)(w >> 8);
    } else {            /* Single byte char */
      if (!w || chk_chr("+,;=[]", w)) { /* Replace illegal chars for SFN */
        w = '_'; cf |= NS_LOSS | NS_LFN;/* Lossy conversion */
      } else {
        if (IsUpper(w)) {   /* ASCII large capital */
          b |= 2;
        } else {
          if (IsLower(w)) { /* ASCII small capital */
            b |= 1; w -= 0x20;
          }
        }
      }
    }
    dj->fn[i++] = (BYTE)w;
  }

  if (dj->fn[0] == DDE) dj->fn[0] = NDDE; /* If the first char collides with deleted mark, replace it with 0x05 */

  if (ni == 8) b <<= 2;
  if ((b & 0x0C) == 0x0C || (b & 0x03) == 0x03) /* Create LFN entry when there are composite capitals */
    cf |= NS_LFN;
  if (!(cf & NS_LFN)) {           /* When LFN is in 8.3 format without extended char, NT flags are created */
    if ((b & 0x03) == 0x01) cf |= NS_EXT; /* NT flag (Extension has only small capital) */
    if ((b & 0x0C) == 0x04) cf |= NS_BODY;  /* NT flag (Filename has only small capital) */
  }

  dj->fn[NS] = cf;  /* SFN is created */

  return FR_OK;


#else /* Non-LFN configuration */
  BYTE b, c, d, *sfn;
  UINT ni, si, i;
  const signed char *p;

  /* Create file name in directory form */
  for (p = *path; *p == '/' || *p == '\\'; p++) ; /* Strip duplicated separator */
  sfn = dj->fn;
  mem_set(sfn, ' ', 11);
  si = i = b = 0; ni = 8;
#if _FS_RPATH
  if (p[si] == '.') { /* Is this a dot entry? */
    for (;;) {
      c = (BYTE)p[si++];
      if (c != '.' || si >= 3) break;
      sfn[i++] = c;
    }
    if (c != '/' && c != '\\' && c > ' ') return FR_INVALID_NAME;
    *path = &p[si];                 /* Return pointer to the next segment */
    sfn[NS] = (c <= ' ') ? NS_LAST | NS_DOT : NS_DOT; /* Set last segment flag if end of path */
    return FR_OK;
  }
#endif
  for (;;) {
    c = (BYTE)p[si++];
    if (c <= ' ' || c == '/' || c == '\\') break; /* Break on end of segment */
    if (c == '.' || i >= ni) {
      if (ni != 8 || c != '.') return FR_INVALID_NAME;
      i = 8; ni = 11;
      b <<= 2; continue;
    }
    if (c >= 0x80) {        /* Extended char? */
      b |= 3;           /* Eliminate NT flag */
#ifdef _EXCVT
      c = excvt[c-0x80];      /* Upper conversion (SBCS) */
#else
#if !_DF1S  /* ASCII only cfg */
      return FR_INVALID_NAME;
#endif
#endif
    }
    if (IsDBCS1(c)) {       /* Check if it is a DBC 1st byte (always false on SBCS cfg) */
      d = (BYTE)p[si++];      /* Get 2nd byte */
      if (!IsDBCS2(d) || i >= ni - 1) /* Reject invalid DBC */
        return FR_INVALID_NAME;
      sfn[i++] = c;
      sfn[i++] = d;
    } else {            /* Single byte code */
      if (chk_chr("\"*+,:;<=>\?[]|\x7F", c))  /* Reject illegal chrs for SFN */
        return FR_INVALID_NAME;
      if (IsUpper(c)) {     /* ASCII large capital? */
        b |= 2;
      } else {
        if (IsLower(c)) {   /* ASCII small capital? */
          b |= 1; c -= 0x20;
        }
      }
      sfn[i++] = c;
    }
  }
  *path = &p[si];           /* Return pointer to the next segment */
  c = (c <= ' ') ? NS_LAST : 0;   /* Set last segment flag if end of path */

  if (!i) return FR_INVALID_NAME;   /* Reject nul string */
  if (sfn[0] == DDE) sfn[0] = NDDE; /* When first char collides with DDE, replace it with 0x05 */

  if (ni == 8) b <<= 2;
  if ((b & 0x03) == 0x01) c |= NS_EXT;  /* NT flag (Name extension has only small capital) */
  if ((b & 0x0C) == 0x04) c |= NS_BODY; /* NT flag (Name body has only small capital) */

  sfn[NS] = c;    /* Store NT flag, File name is created */

  return FR_OK;
#endif
}




/*-----------------------------------------------------------------------*/
/* Get file information from directory entry                             */
/*-----------------------------------------------------------------------*/
#if _FS_MINIMIZE <= 1
static
void get_fileinfo (   /* No return code */
  DIR *dj,      /* Pointer to the directory object */
  FILINFO *fno    /* Pointer to the file information to be filled */
)
{
  UINT i;
  BYTE nt, *dir;
  TCHAR *p, c;


  p = fno->fname;
  if (dj->sect) {
    dir = dj->dir;
    nt = dir[DIR_NTres];    /* NT flag */
    for (i = 0; i < 8; i++) { /* Copy name body */
      c = dir[i];
      if (c == ' ') break;
      if (c == NDDE) c = (TCHAR)DDE;
      if (_USE_LFN && (nt & NS_BODY) && IsUpper(c)) c += 0x20;
#if _LFN_UNICODE
      if (IsDBCS1(c) && i < 7 && IsDBCS2(dir[i+1]))
        c = (c << 8) | dir[++i];
      c = ff_convert(c, 1);
      if (!c) c = '?';
#endif
      *p++ = c;
    }
    if (dir[8] != ' ') {    /* Copy name extension */
      *p++ = '.';
      for (i = 8; i < 11; i++) {
        c = dir[i];
        if (c == ' ') break;
        if (_USE_LFN && (nt & NS_EXT) && IsUpper(c)) c += 0x20;
#if _LFN_UNICODE
        if (IsDBCS1(c) && i < 10 && IsDBCS2(dir[i+1]))
          c = (c << 8) | dir[++i];
        c = ff_convert(c, 1);
        if (!c) c = '?';
#endif
        *p++ = c;
      }
    }
    fno->fattrib = dir[DIR_Attr];       /* Attribute */
    fno->fsize = LD_DWORD(dir+DIR_FileSize);  /* Size */
    fno->fdate = LD_WORD(dir+DIR_WrtDate);    /* Date */
    fno->ftime = LD_WORD(dir+DIR_WrtTime);    /* Time */
  }
  *p = 0;   /* Terminate SFN str by a \0 */

#if _USE_LFN
  if (fno->lfname && fno->lfsize) {
    TCHAR *tp = fno->lfname;
    WCHAR w, *lfn;

    i = 0;
    if (dj->sect && dj->lfn_idx != 0xFFFF) {/* Get LFN if available */
      lfn = dj->lfn;
      while ((w = *lfn++) != 0) {     /* Get an LFN char */
#if !_LFN_UNICODE
        w = ff_convert(w, 0);     /* Unicode -> OEM conversion */
        if (!w) { i = 0; break; }   /* Could not convert, no LFN */
        if (_DF1S && w >= 0x100)    /* Put 1st byte if it is a DBC (always false on SBCS cfg) */
          tp[i++] = (TCHAR)(w >> 8);
#endif
        if (i >= fno->lfsize - 1) { i = 0; break; } /* Buffer overflow, no LFN */
        tp[i++] = (TCHAR)w;
      }
    }
    tp[i] = 0;  /* Terminate the LFN str by a \0 */
  }
#endif
}
#endif /* _FS_MINIMIZE <= 1 */




/*-----------------------------------------------------------------------*/
/* Follow a file path                                                    */
/*-----------------------------------------------------------------------*/

static
FRESULT follow_path ( /* FR_OK(0): successful, !=0: error code */
  DIR *dj,      /* Directory object to return last directory and found object */
  const TCHAR *path /* Full-path string to find a file or directory */
)
{
  FRESULT res;
  BYTE *dir, ns;


#if _FS_RPATH
  if (*path == '/' || *path == '\\') { /* There is a heading separator */
    path++; dj->sclust = 0;   /* Strip it and start from the root dir */
  } else {              /* No heading separator */
    dj->sclust = dj->fs->cdir;  /* Start from the current dir */
  }
#else
  if (*path == '/' || *path == '\\')  /* Strip heading separator if exist */
    path++;
  dj->sclust = 0;           /* Start from the root dir */
#endif

  if ((UINT)*path < ' ') {      /* Nul path means the start directory itself */
    res = dir_sdi(dj, 0);
    dj->dir = 0;

  } else {              /* Follow path */
    for (;;) {
      res = create_name(dj, &path); /* Get a segment */
      if (res != FR_OK) break;
      res = dir_find(dj);       /* Find it */
      ns = *(dj->fn+NS);
      if (res != FR_OK) {       /* Failed to find the object */
        if (res != FR_NO_FILE) break; /* Abort if any hard error occured */
        /* Object not found */
        if (_FS_RPATH && (ns & NS_DOT)) { /* If dot entry is not exit */
          dj->sclust = 0; dj->dir = 0;  /* It is the root dir */
          res = FR_OK;
          if (!(ns & NS_LAST)) continue;
        } else {              /* Could not find the object */
          if (!(ns & NS_LAST)) res = FR_NO_PATH;
        }
        break;
      }
      if (ns & NS_LAST) break;      /* Last segment match. Function completed. */
      dir = dj->dir;            /* There is next segment. Follow the sub directory */
      if (!(dir[DIR_Attr] & AM_DIR)) {  /* Cannot follow because it is a file */
        res = FR_NO_PATH; break;
      }
      dj->sclust = LD_CLUST(dir);
    }
  }

  return res;
}




/*-----------------------------------------------------------------------*/
/* Load a sector and check if it is an FAT Volume Boot Record            */
/*-----------------------------------------------------------------------*/

static
BYTE check_fs ( /* 0:FAT-VBR, 1:Valid BR but not FAT, 2:Not a BR, 3:Disk error */
  FATFS *fs,  /* File system object */
  DWORD sect  /* Sector# (lba) to check if it is an FAT boot record or not */
)
{
  if (disk_read(fs->drv, fs->win, sect, 1) != RES_OK) /* Load boot record */
    return 3;
  if (LD_WORD(&fs->win[BS_55AA]) != 0xAA55)   /* Check record signature (always placed at offset 510 even if the sector size is >512) */
    return 2;

  if ((LD_DWORD(&fs->win[BS_FilSysType]) & 0xFFFFFF) == 0x544146) /* Check "FAT" string */
    return 0;
  if ((LD_DWORD(&fs->win[BS_FilSysType32]) & 0xFFFFFF) == 0x544146)
    return 0;

  return 1;
}




/*-----------------------------------------------------------------------*/
/* Check if the file system object is valid or not                       */
/*-----------------------------------------------------------------------*/

static
FRESULT chk_mounted ( /* FR_OK(0): successful, !=0: any error occurred */
  const TCHAR **path, /* Pointer to pointer to the path name (drive number) */
  FATFS **rfs,    /* Pointer to pointer to the found file system object */
  BYTE chk_wp     /* !=0: Check media write protection for write access */
)
{
  BYTE fmt, b, pi, *tbl;
  UINT vol;
  DSTATUS stat;
  DWORD bsect, fasize, tsect, sysect, nclst, szbfat;
  WORD nrsv;
  const TCHAR *p = *path;
  FATFS *fs;

  /* Get logical drive number from the path name */
  vol = p[0] - '0';         /* Is there a drive number? */
  if (vol <= 9 && p[1] == ':') {    /* Found a drive number, get and strip it */
    p += 2; *path = p;        /* Return pointer to the path name */
  } else {              /* No drive number is given */
#if _FS_RPATH
    vol = CurrVol;          /* Use current drive */
#else
    vol = 0;            /* Use drive 0 */
#endif
  }

  /* Check if the file system object is valid or not */
  if (vol >= _VOLUMES)        /* Is the drive number valid? */
    return FR_INVALID_DRIVE;
  *rfs = fs = FatFs[vol];       /* Return pointer to the corresponding file system object */
  if (!fs) return FR_NOT_ENABLED;   /* Is the file system object available? */

  ENTER_FF(fs);           /* Lock file system */

  if (fs->fs_type) {          /* If the logical drive has been mounted */
    stat = disk_status(fs->drv);
    if (!(stat & STA_NOINIT)) {   /* and the physical drive is kept initialized (has not been changed), */
      if (!_FS_READONLY && chk_wp && (stat & STA_PROTECT))  /* Check write protection if needed */
        return FR_WRITE_PROTECTED;
      return FR_OK;       /* The file system object is valid */
    }
  }

  /* The file system object is not valid. */
  /* Following code attempts to mount the volume. (analyze BPB and initialize the fs object) */

  fs->fs_type = 0;          /* Clear the file system object */
  fs->drv = LD2PD(vol);       /* Bind the logical drive and a physical drive */
  stat = disk_initialize(fs->drv);  /* Initialize low level disk I/O layer */
  if (stat & STA_NOINIT)        /* Check if the initialization succeeded */
    return FR_NOT_READY;      /* Failed to initialize due to no media or hard error */
  if (!_FS_READONLY && chk_wp && (stat & STA_PROTECT))  /* Check disk write protection if needed */
    return FR_WRITE_PROTECTED;
#if _MAX_SS != 512            /* Get disk sector size (variable sector size cfg only) */
  if (disk_ioctl(fs->drv, GET_SECTOR_SIZE, &fs->ssize) != RES_OK)
    return FR_DISK_ERR;
#endif
  /* Search FAT partition on the drive. Supports only generic partitionings, FDISK and SFD. */
  fmt = check_fs(fs, bsect = 0);    /* Load sector 0 and check if it is an FAT-VBR (in SFD) */
  if (LD2PT(vol) && !fmt) fmt = 1;  /* Force non-SFD if the volume is forced partition */
  if (fmt == 1) {           /* Not an FAT-VBR, the physical drive can be partitioned */
    /* Check the partition listed in the partition table */
    pi = LD2PT(vol);
    if (pi) pi--;
    tbl = &fs->win[MBR_Table + pi * SZ_PTE];/* Partition table */
    if (tbl[4]) {           /* Is the partition existing? */
      bsect = LD_DWORD(&tbl[8]);    /* Partition offset in LBA */
      fmt = check_fs(fs, bsect);    /* Check the partition */
    }
  }
  if (fmt == 3) return FR_DISK_ERR;
  if (fmt) return FR_NO_FILESYSTEM;   /* No FAT volume is found */

  /* An FAT volume is found. Following code initializes the file system object */

  if (LD_WORD(fs->win+BPB_BytsPerSec) != SS(fs))    /* (BPB_BytsPerSec must be equal to the physical sector size) */
    return FR_NO_FILESYSTEM;

  fasize = LD_WORD(fs->win+BPB_FATSz16);        /* Number of sectors per FAT */
  if (!fasize) fasize = LD_DWORD(fs->win+BPB_FATSz32);
  fs->fsize = fasize;

  fs->n_fats = b = fs->win[BPB_NumFATs];        /* Number of FAT copies */
  if (b != 1 && b != 2) return FR_NO_FILESYSTEM;    /* (Must be 1 or 2) */
  fasize *= b;                    /* Number of sectors for FAT area */

  fs->csize = b = fs->win[BPB_SecPerClus];      /* Number of sectors per cluster */
  if (!b || (b & (b - 1))) return FR_NO_FILESYSTEM; /* (Must be power of 2) */

  fs->n_rootdir = LD_WORD(fs->win+BPB_RootEntCnt);  /* Number of root directory entries */
  if (fs->n_rootdir % (SS(fs) / SZ_DIR)) return FR_NO_FILESYSTEM; /* (BPB_RootEntCnt must be sector aligned) */

  tsect = LD_WORD(fs->win+BPB_TotSec16);        /* Number of sectors on the volume */
  if (!tsect) tsect = LD_DWORD(fs->win+BPB_TotSec32);

  nrsv = LD_WORD(fs->win+BPB_RsvdSecCnt);       /* Number of reserved sectors */
  if (!nrsv) return FR_NO_FILESYSTEM;         /* (BPB_RsvdSecCnt must not be 0) */

  /* Determine the FAT sub type */
  sysect = nrsv + fasize + fs->n_rootdir / (SS(fs) / SZ_DIR); /* RSV+FAT+DIR */
  if (tsect < sysect) return FR_NO_FILESYSTEM;    /* (Invalid volume size) */
  nclst = (tsect - sysect) / fs->csize;       /* Number of clusters */
  if (!nclst) return FR_NO_FILESYSTEM;        /* (Invalid volume size) */
  fmt = FS_FAT12;
  if (nclst >= MIN_FAT16) fmt = FS_FAT16;
  if (nclst >= MIN_FAT32) fmt = FS_FAT32;

  /* Boundaries and Limits */
  fs->n_fatent = nclst + 2;             /* Number of FAT entries */
  fs->database = bsect + sysect;            /* Data start sector */
  fs->fatbase = bsect + nrsv;             /* FAT start sector */
  if (fmt == FS_FAT32) {
    if (fs->n_rootdir) return FR_NO_FILESYSTEM;   /* (BPB_RootEntCnt must be 0) */
    fs->dirbase = LD_DWORD(fs->win+BPB_RootClus); /* Root directory start cluster */
    szbfat = fs->n_fatent * 4;            /* (Required FAT size) */
  } else {
    if (!fs->n_rootdir) return FR_NO_FILESYSTEM;  /* (BPB_RootEntCnt must not be 0) */
    fs->dirbase = fs->fatbase + fasize;       /* Root directory start sector */
    szbfat = (fmt == FS_FAT16) ?          /* (Required FAT size) */
      fs->n_fatent * 2 : fs->n_fatent * 3 / 2 + (fs->n_fatent & 1);
  }
  if (fs->fsize < (szbfat + (SS(fs) - 1)) / SS(fs)) /* (BPB_FATSz must not be less than required) */
    return FR_NO_FILESYSTEM;

#if !_FS_READONLY
  /* Initialize cluster allocation information */
  fs->free_clust = 0xFFFFFFFF;
  fs->last_clust = 0;

  /* Get fsinfo if available */
  if (fmt == FS_FAT32) {
    fs->fsi_flag = 0;
    fs->fsi_sector = bsect + LD_WORD(fs->win+BPB_FSInfo);
    if (disk_read(fs->drv, fs->win, fs->fsi_sector, 1) == RES_OK &&
      LD_WORD(fs->win+BS_55AA) == 0xAA55 &&
      LD_DWORD(fs->win+FSI_LeadSig) == 0x41615252 &&
      LD_DWORD(fs->win+FSI_StrucSig) == 0x61417272) {
        fs->last_clust = LD_DWORD(fs->win+FSI_Nxt_Free);
        fs->free_clust = LD_DWORD(fs->win+FSI_Free_Count);
    }
  }
#endif
  fs->fs_type = fmt;    /* FAT sub-type */
  fs->id = ++Fsid;    /* File system mount ID */
  fs->winsect = 0;    /* Invalidate sector cache */
  fs->wflag = 0;
#if _FS_RPATH
  fs->cdir = 0;     /* Current directory (root dir) */
#endif
#if _FS_SHARE       /* Clear file lock semaphores */
  clear_lock(fs);
#endif

  return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Check if the file/dir object is valid or not                          */
/*-----------------------------------------------------------------------*/

static
FRESULT validate (  /* FR_OK(0): The object is valid, !=0: Invalid */
  FATFS *fs,    /* Pointer to the file system object */
  WORD id     /* Member id of the target object to be checked */
)
{
  if (!fs || !fs->fs_type || fs->id != id)
    return FR_INVALID_OBJECT;

  ENTER_FF(fs);   /* Lock file system */

  if (disk_status(fs->drv) & STA_NOINIT)
    return FR_NOT_READY;

  return FR_OK;
}




/*--------------------------------------------------------------------------

   Public Functions

--------------------------------------------------------------------------*/



/*-----------------------------------------------------------------------*/
/* Mount/Unmount a Logical Drive                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_mount (
  BYTE vol,   /* Logical drive number to be mounted/unmounted */
  FATFS *fs   /* Pointer to new file system object (NULL for unmount)*/
)
{
  FATFS *rfs;


  if (vol >= _VOLUMES)    /* Check if the drive number is valid */
    return FR_INVALID_DRIVE;
  rfs = FatFs[vol];     /* Get current fs object */

  if (rfs) {
#if _FS_SHARE
    clear_lock(rfs);
#endif
#if _FS_REENTRANT       /* Discard sync object of the current volume */
    if (!ff_del_syncobj(rfs->sobj)) return FR_INT_ERR;
#endif
    rfs->fs_type = 0;   /* Clear old fs object */
  }

  if (fs) {
    fs->fs_type = 0;    /* Clear new fs object */
#if _FS_REENTRANT       /* Create sync object for the new volume */
    if (!ff_cre_syncobj(vol, &fs->sobj)) return FR_INT_ERR;
#endif
  }
  FatFs[vol] = fs;      /* Register new fs object */

  return FR_OK;
}




/*-----------------------------------------------------------------------*/
/* Open or Create a File                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_open (
  FIL *fp,      /* Pointer to the blank file object */
  const TCHAR *path,  /* Pointer to the file name */
  BYTE mode     /* Access mode and file open mode flags */
)
{
  FRESULT res;
  DIR dj;
  BYTE *dir;
  DEF_NAMEBUF;


  fp->fs = 0;     /* Clear file object */

#if !_FS_READONLY
  mode &= FA_READ | FA_WRITE | FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW;
  res = chk_mounted(&path, &dj.fs, (BYTE)(mode & ~FA_READ));
#else
  mode &= FA_READ;
  res = chk_mounted(&path, &dj.fs, 0);
#endif
  INIT_BUF(dj);
  if (res == FR_OK)
    res = follow_path(&dj, path); /* Follow the file path */
  dir = dj.dir;

#if !_FS_READONLY /* R/W configuration */
  if (res == FR_OK) {
    if (!dir) /* Current dir itself */
      res = FR_INVALID_NAME;
#if _FS_SHARE
    else
      res = chk_lock(&dj, (mode & ~FA_READ) ? 1 : 0);
#endif
  }
  /* Create or Open a file */
  if (mode & (FA_CREATE_ALWAYS | FA_OPEN_ALWAYS | FA_CREATE_NEW)) {
    DWORD dw, cl;

    if (res != FR_OK) {         /* No file, create new */
      if (res == FR_NO_FILE)      /* There is no file to open, create a new entry */
#if _FS_SHARE
        res = enq_lock() ? dir_register(&dj) : FR_TOO_MANY_OPEN_FILES;
#else
        res = dir_register(&dj);
#endif
      mode |= FA_CREATE_ALWAYS;   /* File is created */
      dir = dj.dir;         /* New entry */
    }
    else {                /* Any object is already existing */
      if (dir[DIR_Attr] & (AM_RDO | AM_DIR)) {  /* Cannot overwrite it (R/O or DIR) */
        res = FR_DENIED;
      } else {
        if (mode & FA_CREATE_NEW) /* Cannot create as new file */
          res = FR_EXIST;
      }
    }
    if (res == FR_OK && (mode & FA_CREATE_ALWAYS)) {  /* Truncate it if overwrite mode */
      dw = get_fattime();         /* Created time */
      ST_DWORD(dir+DIR_CrtTime, dw);
      dir[DIR_Attr] = 0;          /* Reset attribute */
      ST_DWORD(dir+DIR_FileSize, 0);    /* size = 0 */
      cl = LD_CLUST(dir);         /* Get start cluster */
      ST_CLUST(dir, 0);         /* cluster = 0 */
      dj.fs->wflag = 1;
      if (cl) {             /* Remove the cluster chain if exist */
        dw = dj.fs->winsect;
        res = remove_chain(dj.fs, cl);
        if (res == FR_OK) {
          dj.fs->last_clust = cl - 1; /* Reuse the cluster hole */
          res = move_window(dj.fs, dw);
        }
      }
    }
  }
  else {  /* Open an existing file */
    if (res == FR_OK) {           /* Follow succeeded */
      if (dir[DIR_Attr] & AM_DIR) {   /* It is a directory */
        res = FR_NO_FILE;
      } else {
        if ((mode & FA_WRITE) && (dir[DIR_Attr] & AM_RDO)) /* R/O violation */
          res = FR_DENIED;
      }
    }
  }
  if (res == FR_OK) {
    if (mode & FA_CREATE_ALWAYS)      /* Set file change flag if created or overwritten */
      mode |= FA__WRITTEN;
    fp->dir_sect = dj.fs->winsect;      /* Pointer to the directory entry */
    fp->dir_ptr = dir;
#if _FS_SHARE
    fp->lockid = inc_lock(&dj, (mode & ~FA_READ) ? 1 : 0);
    if (!fp->lockid) res = FR_INT_ERR;
#endif
  }

#else       /* R/O configuration */
  if (res == FR_OK) {         /* Follow succeeded */
    if (!dir) {           /* Current dir itself */
      res = FR_INVALID_NAME;
    } else {
      if (dir[DIR_Attr] & AM_DIR) /* It is a directory */
        res = FR_NO_FILE;
    }
  }
#endif
  FREE_BUF();

  if (res == FR_OK) {
    fp->flag = mode;          /* File access mode */
    fp->sclust = LD_CLUST(dir);     /* File start cluster */
    fp->fsize = LD_DWORD(dir+DIR_FileSize); /* File size */
    fp->fptr = 0;           /* File pointer */
    fp->dsect = 0;
#if _USE_FASTSEEK
    fp->cltbl = 0;            /* Normal seek mode */
#endif
    fp->fs = dj.fs; fp->id = dj.fs->id; /* Validate file object */
  }

  LEAVE_FF(dj.fs, res);
}




/*-----------------------------------------------------------------------*/
/* Read File                                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_read (
  FIL *fp,    /* Pointer to the file object */
  void *buff,   /* Pointer to data buffer */
  UINT btr,   /* Number of bytes to read */
  UINT *br    /* Pointer to number of bytes read */
)
{
  FRESULT res;
  DWORD clst, sect, remain;
  UINT rcnt, cc;
  BYTE csect, *rbuff = buff;


  *br = 0;  /* Initialize byte counter */

  res = validate(fp->fs, fp->id);       /* Check validity */
  if (res != FR_OK) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)         /* Aborted file? */
    LEAVE_FF(fp->fs, FR_INT_ERR);
  if (!(fp->flag & FA_READ))          /* Check access mode */
    LEAVE_FF(fp->fs, FR_DENIED);
  remain = fp->fsize - fp->fptr;
  if (btr > remain) btr = (UINT)remain;   /* Truncate btr by remaining bytes */

  for ( ;  btr;               /* Repeat until all data read */
    rbuff += rcnt, fp->fptr += rcnt, *br += rcnt, btr -= rcnt) {
    if ((fp->fptr % SS(fp->fs)) == 0) {   /* On the sector boundary? */
      csect = (BYTE)(fp->fptr / SS(fp->fs) & (fp->fs->csize - 1));  /* Sector offset in the cluster */
      if (!csect) {           /* On the cluster boundary? */
        if (fp->fptr == 0) {      /* On the top of the file? */
          clst = fp->sclust;      /* Follow from the origin */
        } else {            /* Middle or end of the file */
#if _USE_FASTSEEK
          if (fp->cltbl)
            clst = clmt_clust(fp, fp->fptr);  /* Get cluster# from the CLMT */
          else
#endif
            clst = get_fat(fp->fs, fp->clust);  /* Follow cluster chain on the FAT */
        }
        if (clst < 2) ABORT(fp->fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        fp->clust = clst;       /* Update current cluster */
      }
      sect = clust2sect(fp->fs, fp->clust); /* Get current sector */
      if (!sect) ABORT(fp->fs, FR_INT_ERR);
      sect += csect;
      cc = btr / SS(fp->fs);        /* When remaining bytes >= sector size, */
      if (cc) {             /* Read maximum contiguous sectors directly */
        if (csect + cc > fp->fs->csize) /* Clip at cluster boundary */
          cc = fp->fs->csize - csect;
        if (disk_read(fp->fs->drv, rbuff, sect, (BYTE)cc) != RES_OK)
          ABORT(fp->fs, FR_DISK_ERR);
#if !_FS_READONLY && _FS_MINIMIZE <= 2      /* Replace one of the read sectors with cached data if it contains a dirty sector */
#if _FS_TINY
        if (fp->fs->wflag && fp->fs->winsect - sect < cc)
          mem_cpy(rbuff + ((fp->fs->winsect - sect) * SS(fp->fs)), fp->fs->win, SS(fp->fs));
#else
        if ((fp->flag & FA__DIRTY) && fp->dsect - sect < cc)
          mem_cpy(rbuff + ((fp->dsect - sect) * SS(fp->fs)), fp->buf, SS(fp->fs));
#endif
#endif
        rcnt = SS(fp->fs) * cc;     /* Number of bytes transferred */
        continue;
      }
#if !_FS_TINY
      if (fp->dsect != sect) {      /* Load data sector if not in cache */
#if !_FS_READONLY
        if (fp->flag & FA__DIRTY) {   /* Write-back dirty sector cache */
          if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
            ABORT(fp->fs, FR_DISK_ERR);
          fp->flag &= ~FA__DIRTY;
        }
#endif
        if (disk_read(fp->fs->drv, fp->buf, sect, 1) != RES_OK) /* Fill sector cache */
          ABORT(fp->fs, FR_DISK_ERR);
      }
#endif
      fp->dsect = sect;
    }
    rcnt = SS(fp->fs) - (fp->fptr % SS(fp->fs));  /* Get partial sector data from sector buffer */
    if (rcnt > btr) rcnt = btr;
#if _FS_TINY
    if (move_window(fp->fs, fp->dsect))   /* Move sector window */
      ABORT(fp->fs, FR_DISK_ERR);
    mem_cpy(rbuff, &fp->fs->win[fp->fptr % SS(fp->fs)], rcnt);  /* Pick partial sector */
#else
    mem_cpy(rbuff, &fp->buf[fp->fptr % SS(fp->fs)], rcnt);  /* Pick partial sector */
#endif
  }

  LEAVE_FF(fp->fs, FR_OK);
}




#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Write File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_write (
  FIL *fp,      /* Pointer to the file object */
  const void *buff, /* Pointer to the data to be written */
  UINT btw,     /* Number of bytes to write */
  UINT *bw      /* Pointer to number of bytes written */
)
{
  FRESULT res;
  DWORD clst, sect;
  UINT wcnt, cc;
  const BYTE *wbuff = buff;
  BYTE csect;


  *bw = 0;  /* Initialize byte counter */

  res = validate(fp->fs, fp->id);     /* Check validity */
  if (res != FR_OK) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)       /* Aborted file? */
    LEAVE_FF(fp->fs, FR_INT_ERR);
  if (!(fp->flag & FA_WRITE))       /* Check access mode */
    LEAVE_FF(fp->fs, FR_DENIED);
  if ((DWORD)(fp->fsize + btw) < fp->fsize) btw = 0;  /* File size cannot reach 4GB */

  for ( ;  btw;             /* Repeat until all data written */
    wbuff += wcnt, fp->fptr += wcnt, *bw += wcnt, btw -= wcnt) {
    if ((fp->fptr % SS(fp->fs)) == 0) { /* On the sector boundary? */
      csect = (BYTE)(fp->fptr / SS(fp->fs) & (fp->fs->csize - 1));  /* Sector offset in the cluster */
      if (!csect) {         /* On the cluster boundary? */
        if (fp->fptr == 0) {    /* On the top of the file? */
          clst = fp->sclust;    /* Follow from the origin */
          if (clst == 0)      /* When no cluster is allocated, */
            fp->sclust = clst = create_chain(fp->fs, 0);  /* Create a new cluster chain */
        } else {          /* Middle or end of the file */
#if _USE_FASTSEEK
          if (fp->cltbl)
            clst = clmt_clust(fp, fp->fptr);  /* Get cluster# from the CLMT */
          else
#endif
            clst = create_chain(fp->fs, fp->clust); /* Follow or stretch cluster chain on the FAT */
        }
        if (clst == 0) break;   /* Could not allocate a new cluster (disk full) */
        if (clst == 1) ABORT(fp->fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        fp->clust = clst;     /* Update current cluster */
      }
#if _FS_TINY
      if (fp->fs->winsect == fp->dsect && move_window(fp->fs, 0)) /* Write-back sector cache */
        ABORT(fp->fs, FR_DISK_ERR);
#else
      if (fp->flag & FA__DIRTY) {   /* Write-back sector cache */
        if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
          ABORT(fp->fs, FR_DISK_ERR);
        fp->flag &= ~FA__DIRTY;
      }
#endif
      sect = clust2sect(fp->fs, fp->clust); /* Get current sector */
      if (!sect) ABORT(fp->fs, FR_INT_ERR);
      sect += csect;
      cc = btw / SS(fp->fs);      /* When remaining bytes >= sector size, */
      if (cc) {           /* Write maximum contiguous sectors directly */
        if (csect + cc > fp->fs->csize) /* Clip at cluster boundary */
          cc = fp->fs->csize - csect;
        if (disk_write(fp->fs->drv, wbuff, sect, (BYTE)cc) != RES_OK)
          ABORT(fp->fs, FR_DISK_ERR);
#if _FS_TINY
        if (fp->fs->winsect - sect < cc) {  /* Refill sector cache if it gets invalidated by the direct write */
          mem_cpy(fp->fs->win, wbuff + ((fp->fs->winsect - sect) * SS(fp->fs)), SS(fp->fs));
          fp->fs->wflag = 0;
        }
#else
        if (fp->dsect - sect < cc) { /* Refill sector cache if it gets invalidated by the direct write */
          mem_cpy(fp->buf, wbuff + ((fp->dsect - sect) * SS(fp->fs)), SS(fp->fs));
          fp->flag &= ~FA__DIRTY;
        }
#endif
        wcnt = SS(fp->fs) * cc;   /* Number of bytes transferred */
        continue;
      }
#if _FS_TINY
      if (fp->fptr >= fp->fsize) {  /* Avoid silly cache filling at growing edge */
        if (move_window(fp->fs, 0)) ABORT(fp->fs, FR_DISK_ERR);
        fp->fs->winsect = sect;
      }
#else
      if (fp->dsect != sect) {    /* Fill sector cache with file data */
        if (fp->fptr < fp->fsize &&
          disk_read(fp->fs->drv, fp->buf, sect, 1) != RES_OK)
            ABORT(fp->fs, FR_DISK_ERR);
      }
#endif
      fp->dsect = sect;
    }
    wcnt = SS(fp->fs) - (fp->fptr % SS(fp->fs));/* Put partial sector into file I/O buffer */
    if (wcnt > btw) wcnt = btw;
#if _FS_TINY
    if (move_window(fp->fs, fp->dsect)) /* Move sector window */
      ABORT(fp->fs, FR_DISK_ERR);
    mem_cpy(&fp->fs->win[fp->fptr % SS(fp->fs)], wbuff, wcnt);  /* Fit partial sector */
    fp->fs->wflag = 1;
#else
    mem_cpy(&fp->buf[fp->fptr % SS(fp->fs)], wbuff, wcnt);  /* Fit partial sector */
    fp->flag |= FA__DIRTY;
#endif
  }

  if (fp->fptr > fp->fsize) fp->fsize = fp->fptr; /* Update file size if needed */
  fp->flag |= FA__WRITTEN;            /* Set file change flag */

  LEAVE_FF(fp->fs, FR_OK);
}




/*-----------------------------------------------------------------------*/
/* Synchronize the File Object                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_sync (
  FIL *fp   /* Pointer to the file object */
)
{
  FRESULT res;
  DWORD tim;
  BYTE *dir;


  res = validate(fp->fs, fp->id);   /* Check validity of the object */
  if (res == FR_OK) {
    if (fp->flag & FA__WRITTEN) { /* Has the file been written? */
#if !_FS_TINY /* Write-back dirty buffer */
      if (fp->flag & FA__DIRTY) {
        if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
          LEAVE_FF(fp->fs, FR_DISK_ERR);
        fp->flag &= ~FA__DIRTY;
      }
#endif
      /* Update the directory entry */
      res = move_window(fp->fs, fp->dir_sect);
      if (res == FR_OK) {
        dir = fp->dir_ptr;
        dir[DIR_Attr] |= AM_ARC;          /* Set archive bit */
        ST_DWORD(dir+DIR_FileSize, fp->fsize);    /* Update file size */
        ST_CLUST(dir, fp->sclust);          /* Update start cluster */
        tim = get_fattime();            /* Update updated time */
        ST_DWORD(dir+DIR_WrtTime, tim);
        fp->flag &= ~FA__WRITTEN;
        fp->fs->wflag = 1;
        res = sync(fp->fs);
      }
    }
  }

  LEAVE_FF(fp->fs, res);
}

#endif /* !_FS_READONLY */




/*-----------------------------------------------------------------------*/
/* Close File                                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_close (
  FIL *fp   /* Pointer to the file object to be closed */
)
{
  FRESULT res;

#if _FS_READONLY
  FATFS *fs = fp->fs;
  res = validate(fs, fp->id);
  if (res == FR_OK) fp->fs = 0; /* Discard file object */
  LEAVE_FF(fs, res);

#else
  res = f_sync(fp);   /* Flush cached data */
#if _FS_SHARE
  if (res == FR_OK) {   /* Decrement open counter */
#if _FS_REENTRANT
    res = validate(fp->fs, fp->id);
    if (res == FR_OK) {
      res = dec_lock(fp->lockid);
      unlock_fs(fp->fs, FR_OK);
    }
#else
    res = dec_lock(fp->lockid);
#endif
  }
#endif
  if (res == FR_OK) fp->fs = 0; /* Discard file object */
  return res;
#endif
}




/*-----------------------------------------------------------------------*/
/* Current Drive/Directory Handlings                                     */
/*-----------------------------------------------------------------------*/

#if _FS_RPATH >= 1

FRESULT f_chdrive (
  BYTE drv    /* Drive number */
)
{
  if (drv >= _VOLUMES) return FR_INVALID_DRIVE;

  CurrVol = drv;

  return FR_OK;
}



FRESULT f_chdir (
  const TCHAR *path /* Pointer to the directory path */
)
{
  FRESULT res;
  DIR dj;
  DEF_NAMEBUF;


  res = chk_mounted(&path, &dj.fs, 0);
  if (res == FR_OK) {
    INIT_BUF(dj);
    res = follow_path(&dj, path);   /* Follow the path */
    FREE_BUF();
    if (res == FR_OK) {         /* Follow completed */
      if (!dj.dir) {
        dj.fs->cdir = dj.sclust;  /* Start directory itself */
      } else {
        if (dj.dir[DIR_Attr] & AM_DIR)  /* Reached to the directory */
          dj.fs->cdir = LD_CLUST(dj.dir);
        else
          res = FR_NO_PATH;   /* Reached but a file */
      }
    }
    if (res == FR_NO_FILE) res = FR_NO_PATH;
  }

  LEAVE_FF(dj.fs, res);
}


#if _FS_RPATH >= 2
FRESULT f_getcwd (
  TCHAR *path,  /* Pointer to the directory path */
  UINT sz_path  /* Size of path */
)
{
  FRESULT res;
  DIR dj;
  UINT i, n;
  DWORD ccl;
  TCHAR *tp;
  FILINFO fno;
  DEF_NAMEBUF;


  *path = 0;
  res = chk_mounted((const TCHAR**)&path, &dj.fs, 0); /* Get current volume */
  if (res == FR_OK) {
    INIT_BUF(dj);
    i = sz_path;    /* Bottom of buffer (dir stack base) */
    dj.sclust = dj.fs->cdir;      /* Start to follow upper dir from current dir */
    while ((ccl = dj.sclust) != 0) {  /* Repeat while current dir is a sub-dir */
      res = dir_sdi(&dj, 1);      /* Get parent dir */
      if (res != FR_OK) break;
      res = dir_read(&dj);
      if (res != FR_OK) break;
      dj.sclust = LD_CLUST(dj.dir); /* Goto parent dir */
      res = dir_sdi(&dj, 0);
      if (res != FR_OK) break;
      do {              /* Find the entry links to the child dir */
        res = dir_read(&dj);
        if (res != FR_OK) break;
        if (ccl == LD_CLUST(dj.dir)) break; /* Found the entry */
        res = dir_next(&dj, 0);
      } while (res == FR_OK);
      if (res == FR_NO_FILE) res = FR_INT_ERR;/* It cannot be 'not found'. */
      if (res != FR_OK) break;
#if _USE_LFN
      fno.lfname = path;
      fno.lfsize = i;
#endif
      get_fileinfo(&dj, &fno);    /* Get the dir name and push it to the buffer */
      tp = fno.fname;
      if (_USE_LFN && *path) tp = path;
      for (n = 0; tp[n]; n++) ;
      if (i < n + 3) {
        res = FR_NOT_ENOUGH_CORE; break;
      }
      while (n) path[--i] = tp[--n];
      path[--i] = '/';
    }
    tp = path;
    if (res == FR_OK) {
      *tp++ = '0' + CurrVol;      /* Put drive number */
      *tp++ = ':';
      if (i == sz_path) {       /* Root-dir */
        *tp++ = '/';
      } else {            /* Sub-dir */
        do    /* Add stacked path str */
          *tp++ = path[i++];
        while (i < sz_path);
      }
    }
    *tp = 0;
    FREE_BUF();
  }

  LEAVE_FF(dj.fs, res);
}
#endif /* _FS_RPATH >= 2 */
#endif /* _FS_RPATH >= 1 */



#if _FS_MINIMIZE <= 2
/*-----------------------------------------------------------------------*/
/* Seek File R/W Pointer                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_lseek (
  FIL *fp,    /* Pointer to the file object */
  DWORD ofs   /* File pointer from top of file */
)
{
  FRESULT res;


  res = validate(fp->fs, fp->id);   /* Check validity of the object */
  if (res != FR_OK) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)     /* Check abort flag */
    LEAVE_FF(fp->fs, FR_INT_ERR);

#if _USE_FASTSEEK
  if (fp->cltbl) {  /* Fast seek */
    DWORD cl, pcl, ncl, tcl, dsc, tlen, ulen, *tbl;

    if (ofs == CREATE_LINKMAP) {  /* Create CLMT */
      tbl = fp->cltbl;
      tlen = *tbl++; ulen = 2;  /* Given table size and required table size */
      cl = fp->sclust;      /* Top of the chain */
      if (cl) {
        do {
          /* Get a fragment */
          tcl = cl; ncl = 0; ulen += 2; /* Top, length and used items */
          do {
            pcl = cl; ncl++;
            cl = get_fat(fp->fs, cl);
            if (cl <= 1) ABORT(fp->fs, FR_INT_ERR);
            if (cl == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
          } while (cl == pcl + 1);
          if (ulen <= tlen) {   /* Store the length and top of the fragment */
            *tbl++ = ncl; *tbl++ = tcl;
          }
        } while (cl < fp->fs->n_fatent);  /* Repeat until end of chain */
      }
      *fp->cltbl = ulen;  /* Number of items used */
      if (ulen <= tlen)
        *tbl = 0;   /* Terminate table */
      else
        res = FR_NOT_ENOUGH_CORE; /* Given table size is smaller than required */

    } else {            /* Fast seek */
      if (ofs > fp->fsize)    /* Clip offset at the file size */
        ofs = fp->fsize;
      fp->fptr = ofs;       /* Set file pointer */
      if (ofs) {
        fp->clust = clmt_clust(fp, ofs - 1);
        dsc = clust2sect(fp->fs, fp->clust);
        if (!dsc) ABORT(fp->fs, FR_INT_ERR);
        dsc += (ofs - 1) / SS(fp->fs) & (fp->fs->csize - 1);
        if (fp->fptr % SS(fp->fs) && dsc != fp->dsect) {  /* Refill sector cache if needed */
#if !_FS_TINY
#if !_FS_READONLY
          if (fp->flag & FA__DIRTY) {   /* Write-back dirty sector cache */
            if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
              ABORT(fp->fs, FR_DISK_ERR);
            fp->flag &= ~FA__DIRTY;
          }
#endif
          if (disk_read(fp->fs->drv, fp->buf, dsc, 1) != RES_OK)  /* Load current sector */
            ABORT(fp->fs, FR_DISK_ERR);
#endif
          fp->dsect = dsc;
        }
      }
    }
  } else
#endif

  /* Normal Seek */
  {
    DWORD clst, bcs, nsect, ifptr;

    if (ofs > fp->fsize         /* In read-only mode, clip offset with the file size */
#if !_FS_READONLY
       && !(fp->flag & FA_WRITE)
#endif
      ) ofs = fp->fsize;

    ifptr = fp->fptr;
    fp->fptr = nsect = 0;
    if (ofs) {
      bcs = (DWORD)fp->fs->csize * SS(fp->fs);  /* Cluster size (byte) */
      if (ifptr > 0 &&
        (ofs - 1) / bcs >= (ifptr - 1) / bcs) { /* When seek to same or following cluster, */
        fp->fptr = (ifptr - 1) & ~(bcs - 1);  /* start from the current cluster */
        ofs -= fp->fptr;
        clst = fp->clust;
      } else {                  /* When seek to back cluster, */
        clst = fp->sclust;            /* start from the first cluster */
#if !_FS_READONLY
        if (clst == 0) {            /* If no cluster chain, create a new chain */
          clst = create_chain(fp->fs, 0);
          if (clst == 1) ABORT(fp->fs, FR_INT_ERR);
          if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
          fp->sclust = clst;
        }
#endif
        fp->clust = clst;
      }
      if (clst != 0) {
        while (ofs > bcs) {           /* Cluster following loop */
#if !_FS_READONLY
          if (fp->flag & FA_WRITE) {      /* Check if in write mode or not */
            clst = create_chain(fp->fs, clst);  /* Force stretch if in write mode */
            if (clst == 0) {        /* When disk gets full, clip file size */
              ofs = bcs; break;
            }
          } else
#endif
            clst = get_fat(fp->fs, clst); /* Follow cluster chain if not in write mode */
          if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
          if (clst <= 1 || clst >= fp->fs->n_fatent) ABORT(fp->fs, FR_INT_ERR);
          fp->clust = clst;
          fp->fptr += bcs;
          ofs -= bcs;
        }
        fp->fptr += ofs;
        if (ofs % SS(fp->fs)) {
          nsect = clust2sect(fp->fs, clst); /* Current sector */
          if (!nsect) ABORT(fp->fs, FR_INT_ERR);
          nsect += ofs / SS(fp->fs);
        }
      }
    }
    if (fp->fptr % SS(fp->fs) && nsect != fp->dsect) {  /* Fill sector cache if needed */
#if !_FS_TINY
#if !_FS_READONLY
      if (fp->flag & FA__DIRTY) {     /* Write-back dirty sector cache */
        if (disk_write(fp->fs->drv, fp->buf, fp->dsect, 1) != RES_OK)
          ABORT(fp->fs, FR_DISK_ERR);
        fp->flag &= ~FA__DIRTY;
      }
#endif
      if (disk_read(fp->fs->drv, fp->buf, nsect, 1) != RES_OK)  /* Fill sector cache */
        ABORT(fp->fs, FR_DISK_ERR);
#endif
      fp->dsect = nsect;
    }
#if !_FS_READONLY
    if (fp->fptr > fp->fsize) {     /* Set file change flag if the file size is extended */
      fp->fsize = fp->fptr;
      fp->flag |= FA__WRITTEN;
    }
#endif
  }

  LEAVE_FF(fp->fs, res);
}



#if _FS_MINIMIZE <= 1
/*-----------------------------------------------------------------------*/
/* Create a Directroy Object                                             */
/*-----------------------------------------------------------------------*/

FRESULT f_opendir (
  DIR *dj,      /* Pointer to directory object to create */
  const TCHAR *path /* Pointer to the directory path */
)
{
  FRESULT res;
  DEF_NAMEBUF;


  res = chk_mounted(&path, &dj->fs, 0);
  if (res == FR_OK) {
    INIT_BUF(*dj);
    res = follow_path(dj, path);      /* Follow the path to the directory */
    FREE_BUF();
    if (res == FR_OK) {           /* Follow completed */
      if (dj->dir) {            /* It is not the root dir */
        if (dj->dir[DIR_Attr] & AM_DIR) { /* The object is a directory */
          dj->sclust = LD_CLUST(dj->dir);
        } else {            /* The object is not a directory */
          res = FR_NO_PATH;
        }
      }
      if (res == FR_OK) {
        dj->id = dj->fs->id;
        res = dir_sdi(dj, 0);     /* Rewind dir */
      }
    }
    if (res == FR_NO_FILE) res = FR_NO_PATH;
  }

  LEAVE_FF(dj->fs, res);
}




/*-----------------------------------------------------------------------*/
/* Read Directory Entry in Sequense                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_readdir (
  DIR *dj,      /* Pointer to the open directory object */
  FILINFO *fno    /* Pointer to file information to return */
)
{
  FRESULT res;
  DEF_NAMEBUF;


  res = validate(dj->fs, dj->id);     /* Check validity of the object */
  if (res == FR_OK) {
    if (!fno) {
      res = dir_sdi(dj, 0);     /* Rewind the directory object */
    } else {
      INIT_BUF(*dj);
      res = dir_read(dj);       /* Read an directory item */
      if (res == FR_NO_FILE) {    /* Reached end of dir */
        dj->sect = 0;
        res = FR_OK;
      }
      if (res == FR_OK) {       /* A valid entry is found */
        get_fileinfo(dj, fno);    /* Get the object information */
        res = dir_next(dj, 0);    /* Increment index for next */
        if (res == FR_NO_FILE) {
          dj->sect = 0;
          res = FR_OK;
        }
      }
      FREE_BUF();
    }
  }

  LEAVE_FF(dj->fs, res);
}



#if _FS_MINIMIZE == 0
/*-----------------------------------------------------------------------*/
/* Get File Status                                                       */
/*-----------------------------------------------------------------------*/

FRESULT f_stat (
  const TCHAR *path,  /* Pointer to the file path */
  FILINFO *fno    /* Pointer to file information to return */
)
{
  FRESULT res;
  DIR dj;
  DEF_NAMEBUF;


  res = chk_mounted(&path, &dj.fs, 0);
  if (res == FR_OK) {
    INIT_BUF(dj);
    res = follow_path(&dj, path); /* Follow the file path */
    if (res == FR_OK) {       /* Follow completed */
      if (dj.dir)   /* Found an object */
        get_fileinfo(&dj, fno);
      else      /* It is root dir */
        res = FR_INVALID_NAME;
    }
    FREE_BUF();
  }

  LEAVE_FF(dj.fs, res);
}



#if !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Get Number of Free Clusters                                           */
/*-----------------------------------------------------------------------*/

FRESULT f_getfree (
  const TCHAR *path,  /* Pointer to the logical drive number (root dir) */
  DWORD *nclst,   /* Pointer to the variable to return number of free clusters */
  FATFS **fatfs   /* Pointer to pointer to corresponding file system object to return */
)
{
  FRESULT res;
  DWORD n, clst, sect, stat;
  UINT i;
  BYTE fat, *p;


  /* Get drive number */
  res = chk_mounted(&path, fatfs, 0);
  if (res == FR_OK) {
    /* If free_clust is valid, return it without full cluster scan */
    if ((*fatfs)->free_clust <= (*fatfs)->n_fatent - 2) {
      *nclst = (*fatfs)->free_clust;
    } else {
      /* Get number of free clusters */
      fat = (*fatfs)->fs_type;
      n = 0;
      if (fat == FS_FAT12) {
        clst = 2;
        do {
          stat = get_fat(*fatfs, clst);
          if (stat == 0xFFFFFFFF) { res = FR_DISK_ERR; break; }
          if (stat == 1) { res = FR_INT_ERR; break; }
          if (stat == 0) n++;
        } while (++clst < (*fatfs)->n_fatent);
      } else {
        clst = (*fatfs)->n_fatent;
        sect = (*fatfs)->fatbase;
        i = 0; p = 0;
        do {
          if (!i) {
            res = move_window(*fatfs, sect++);
            if (res != FR_OK) break;
            p = (*fatfs)->win;
            i = SS(*fatfs);
          }
          if (fat == FS_FAT16) {
            if (LD_WORD(p) == 0) n++;
            p += 2; i -= 2;
          } else {
            if ((LD_DWORD(p) & 0x0FFFFFFF) == 0) n++;
            p += 4; i -= 4;
          }
        } while (--clst);
      }
      (*fatfs)->free_clust = n;
      if (fat == FS_FAT32) (*fatfs)->fsi_flag = 1;
      *nclst = n;
    }
  }
  LEAVE_FF(*fatfs, res);
}




/*-----------------------------------------------------------------------*/
/* Truncate File                                                         */
/*-----------------------------------------------------------------------*/

FRESULT f_truncate (
  FIL *fp   /* Pointer to the file object */
)
{
  FRESULT res;
  DWORD ncl;


  res = validate(fp->fs, fp->id);   /* Check validity of the object */
  if (res == FR_OK) {
    if (fp->flag & FA__ERROR) {     /* Check abort flag */
      res = FR_INT_ERR;
    } else {
      if (!(fp->flag & FA_WRITE))   /* Check access mode */
        res = FR_DENIED;
    }
  }
  if (res == FR_OK) {
    if (fp->fsize > fp->fptr) {
      fp->fsize = fp->fptr; /* Set file size to current R/W point */
      fp->flag |= FA__WRITTEN;
      if (fp->fptr == 0) {  /* When set file size to zero, remove entire cluster chain */
        res = remove_chain(fp->fs, fp->sclust);
        fp->sclust = 0;
      } else {        /* When truncate a part of the file, remove remaining clusters */
        ncl = get_fat(fp->fs, fp->clust);
        res = FR_OK;
        if (ncl == 0xFFFFFFFF) res = FR_DISK_ERR;
        if (ncl == 1) res = FR_INT_ERR;
        if (res == FR_OK && ncl < fp->fs->n_fatent) {
          res = put_fat(fp->fs, fp->clust, 0x0FFFFFFF);
          if (res == FR_OK) res = remove_chain(fp->fs, ncl);
        }
      }
    }
    if (res != FR_OK) fp->flag |= FA__ERROR;
  }

  LEAVE_FF(fp->fs, res);
}




/*-----------------------------------------------------------------------*/
/* Delete a File or Directory                                            */
/*-----------------------------------------------------------------------*/

FRESULT f_unlink (
  const TCHAR *path   /* Pointer to the file or directory path */
)
{
  FRESULT res;
  DIR dj, sdj;
  BYTE *dir;
  DWORD dclst;
  DEF_NAMEBUF;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res == FR_OK) {
    INIT_BUF(dj);
    res = follow_path(&dj, path);   /* Follow the file path */
    if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;      /* Cannot remove dot entry */
#if _FS_SHARE
    if (res == FR_OK) res = chk_lock(&dj, 2); /* Cannot remove open file */
#endif
    if (res == FR_OK) {         /* The object is accessible */
      dir = dj.dir;
      if (!dir) {
        res = FR_INVALID_NAME;    /* Cannot remove the start directory */
      } else {
        if (dir[DIR_Attr] & AM_RDO)
          res = FR_DENIED;    /* Cannot remove R/O object */
      }
      dclst = LD_CLUST(dir);
      if (res == FR_OK && (dir[DIR_Attr] & AM_DIR)) { /* Is it a sub-dir? */
        if (dclst < 2) {
          res = FR_INT_ERR;
        } else {
          mem_cpy(&sdj, &dj, sizeof(DIR));  /* Check if the sub-dir is empty or not */
          sdj.sclust = dclst;
          res = dir_sdi(&sdj, 2);   /* Exclude dot entries */
          if (res == FR_OK) {
            res = dir_read(&sdj);
            if (res == FR_OK      /* Not empty dir */
#if _FS_RPATH
            || dclst == sdj.fs->cdir  /* Current dir */
#endif
            ) res = FR_DENIED;
            if (res == FR_NO_FILE) res = FR_OK; /* Empty */
          }
        }
      }
      if (res == FR_OK) {
        res = dir_remove(&dj);    /* Remove the directory entry */
        if (res == FR_OK) {
          if (dclst)        /* Remove the cluster chain if exist */
            res = remove_chain(dj.fs, dclst);
          if (res == FR_OK) res = sync(dj.fs);
        }
      }
    }
    FREE_BUF();
  }
  LEAVE_FF(dj.fs, res);
}




/*-----------------------------------------------------------------------*/
/* Create a Directory                                                    */
/*-----------------------------------------------------------------------*/

FRESULT f_mkdir (
  const TCHAR *path   /* Pointer to the directory path */
)
{
  FRESULT res;
  DIR dj;
  BYTE *dir, n;
  DWORD dsc, dcl, pcl, tim = get_fattime();
  DEF_NAMEBUF;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res == FR_OK) {
    INIT_BUF(dj);
    res = follow_path(&dj, path);     /* Follow the file path */
    if (res == FR_OK) res = FR_EXIST;   /* Any object with same name is already existing */
    if (_FS_RPATH && res == FR_NO_FILE && (dj.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;
    if (res == FR_NO_FILE) {        /* Can create a new directory */
      dcl = create_chain(dj.fs, 0);   /* Allocate a cluster for the new directory table */
      res = FR_OK;
      if (dcl == 0) res = FR_DENIED;    /* No space to allocate a new cluster */
      if (dcl == 1) res = FR_INT_ERR;
      if (dcl == 0xFFFFFFFF) res = FR_DISK_ERR;
      if (res == FR_OK)         /* Flush FAT */
        res = move_window(dj.fs, 0);
      if (res == FR_OK) {         /* Initialize the new directory table */
        dsc = clust2sect(dj.fs, dcl);
        dir = dj.fs->win;
        mem_set(dir, 0, SS(dj.fs));
        mem_set(dir+DIR_Name, ' ', 8+3);  /* Create "." entry */
        dir[DIR_Name] = '.';
        dir[DIR_Attr] = AM_DIR;
        ST_DWORD(dir+DIR_WrtTime, tim);
        ST_CLUST(dir, dcl);
        mem_cpy(dir+SZ_DIR, dir, SZ_DIR);   /* Create ".." entry */
        dir[33] = '.'; pcl = dj.sclust;
        if (dj.fs->fs_type == FS_FAT32 && pcl == dj.fs->dirbase)
          pcl = 0;
        ST_CLUST(dir+SZ_DIR, pcl);
        for (n = dj.fs->csize; n; n--) {  /* Write dot entries and clear following sectors */
          dj.fs->winsect = dsc++;
          dj.fs->wflag = 1;
          res = move_window(dj.fs, 0);
          if (res != FR_OK) break;
          mem_set(dir, 0, SS(dj.fs));
        }
      }
      if (res == FR_OK) res = dir_register(&dj);  /* Register the object to the directoy */
      if (res != FR_OK) {
        remove_chain(dj.fs, dcl);     /* Could not register, remove cluster chain */
      } else {
        dir = dj.dir;
        dir[DIR_Attr] = AM_DIR;       /* Attribute */
        ST_DWORD(dir+DIR_WrtTime, tim);   /* Created time */
        ST_CLUST(dir, dcl);         /* Table start cluster */
        dj.fs->wflag = 1;
        res = sync(dj.fs);
      }
    }
    FREE_BUF();
  }

  LEAVE_FF(dj.fs, res);
}




/*-----------------------------------------------------------------------*/
/* Change Attribute                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_chmod (
  const TCHAR *path,  /* Pointer to the file path */
  BYTE value,     /* Attribute bits */
  BYTE mask     /* Attribute mask to change */
)
{
  FRESULT res;
  DIR dj;
  BYTE *dir;
  DEF_NAMEBUF;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res == FR_OK) {
    INIT_BUF(dj);
    res = follow_path(&dj, path);   /* Follow the file path */
    FREE_BUF();
    if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;
    if (res == FR_OK) {
      dir = dj.dir;
      if (!dir) {           /* Is it a root directory? */
        res = FR_INVALID_NAME;
      } else {            /* File or sub directory */
        mask &= AM_RDO|AM_HID|AM_SYS|AM_ARC;  /* Valid attribute mask */
        dir[DIR_Attr] = (value & mask) | (dir[DIR_Attr] & (BYTE)~mask); /* Apply attribute change */
        dj.fs->wflag = 1;
        res = sync(dj.fs);
      }
    }
  }

  LEAVE_FF(dj.fs, res);
}




/*-----------------------------------------------------------------------*/
/* Change Timestamp                                                      */
/*-----------------------------------------------------------------------*/

FRESULT f_utime (
  const TCHAR *path,  /* Pointer to the file/directory name */
  const FILINFO *fno  /* Pointer to the time stamp to be set */
)
{
  FRESULT res;
  DIR dj;
  BYTE *dir;
  DEF_NAMEBUF;


  res = chk_mounted(&path, &dj.fs, 1);
  if (res == FR_OK) {
    INIT_BUF(dj);
    res = follow_path(&dj, path); /* Follow the file path */
    FREE_BUF();
    if (_FS_RPATH && res == FR_OK && (dj.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;
    if (res == FR_OK) {
      dir = dj.dir;
      if (!dir) {         /* Root directory */
        res = FR_INVALID_NAME;
      } else {          /* File or sub-directory */
        ST_WORD(dir+DIR_WrtTime, fno->ftime);
        ST_WORD(dir+DIR_WrtDate, fno->fdate);
        dj.fs->wflag = 1;
        res = sync(dj.fs);
      }
    }
  }

  LEAVE_FF(dj.fs, res);
}




/*-----------------------------------------------------------------------*/
/* Rename File/Directory                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_rename (
  const TCHAR *path_old,  /* Pointer to the old name */
  const TCHAR *path_new /* Pointer to the new name */
)
{
  FRESULT res;
  DIR djo, djn;
  BYTE buf[21], *dir;
  DWORD dw;
  DEF_NAMEBUF;


  res = chk_mounted(&path_old, &djo.fs, 1);
  if (res == FR_OK) {
    djn.fs = djo.fs;
    INIT_BUF(djo);
    res = follow_path(&djo, path_old);    /* Check old object */
    if (_FS_RPATH && res == FR_OK && (djo.fn[NS] & NS_DOT))
      res = FR_INVALID_NAME;
#if _FS_SHARE
    if (res == FR_OK) res = chk_lock(&djo, 2);
#endif
    if (res == FR_OK) {           /* Old object is found */
      if (!djo.dir) {           /* Is root dir? */
        res = FR_NO_FILE;
      } else {
        mem_cpy(buf, djo.dir+DIR_Attr, 21);   /* Save the object information except for name */
        mem_cpy(&djn, &djo, sizeof(DIR));   /* Check new object */
        res = follow_path(&djn, path_new);
        if (res == FR_OK) res = FR_EXIST;   /* The new object name is already existing */
        if (res == FR_NO_FILE) {        /* Is it a valid path and no name collision? */
/* Start critical section that any interruption or error can cause cross-link */
          res = dir_register(&djn);     /* Register the new entry */
          if (res == FR_OK) {
            dir = djn.dir;          /* Copy object information except for name */
            mem_cpy(dir+13, buf+2, 19);
            dir[DIR_Attr] = buf[0] | AM_ARC;
            djo.fs->wflag = 1;
            if (djo.sclust != djn.sclust && (dir[DIR_Attr] & AM_DIR)) {   /* Update .. entry in the directory if needed */
              dw = clust2sect(djn.fs, LD_CLUST(dir));
              if (!dw) {
                res = FR_INT_ERR;
              } else {
                res = move_window(djn.fs, dw);
                dir = djn.fs->win+SZ_DIR; /* .. entry */
                if (res == FR_OK && dir[1] == '.') {
                  dw = (djn.fs->fs_type == FS_FAT32 && djn.sclust == djn.fs->dirbase) ? 0 : djn.sclust;
                  ST_CLUST(dir, dw);
                  djn.fs->wflag = 1;
                }
              }
            }
            if (res == FR_OK) {
              res = dir_remove(&djo);   /* Remove old entry */
              if (res == FR_OK)
                res = sync(djo.fs);
            }
          }
/* End critical section */
        }
      }
    }
    FREE_BUF();
  }
  LEAVE_FF(djo.fs, res);
}

#endif /* !_FS_READONLY */
#endif /* _FS_MINIMIZE == 0 */
#endif /* _FS_MINIMIZE <= 1 */
#endif /* _FS_MINIMIZE <= 2 */



/*-----------------------------------------------------------------------*/
/* Forward data to the stream directly (available on only tiny cfg)      */
/*-----------------------------------------------------------------------*/
#if _USE_FORWARD && _FS_TINY

FRESULT f_forward (
  FIL *fp,            /* Pointer to the file object */
  UINT (*func)(const BYTE*,UINT), /* Pointer to the streaming function */
  UINT btr,           /* Number of bytes to forward */
  UINT *bf            /* Pointer to number of bytes forwarded */
)
{
  FRESULT res;
  DWORD remain, clst, sect;
  UINT rcnt;
  BYTE csect;


  *bf = 0;  /* Initialize byte counter */

  res = validate(fp->fs, fp->id);         /* Check validity of the object */
  if (res != FR_OK) LEAVE_FF(fp->fs, res);
  if (fp->flag & FA__ERROR)           /* Check error flag */
    LEAVE_FF(fp->fs, FR_INT_ERR);
  if (!(fp->flag & FA_READ))            /* Check access mode */
    LEAVE_FF(fp->fs, FR_DENIED);

  remain = fp->fsize - fp->fptr;
  if (btr > remain) btr = (UINT)remain;     /* Truncate btr by remaining bytes */

  for ( ;  btr && (*func)(0, 0);          /* Repeat until all data transferred or stream becomes busy */
    fp->fptr += rcnt, *bf += rcnt, btr -= rcnt) {
    csect = (BYTE)(fp->fptr / SS(fp->fs) & (fp->fs->csize - 1));  /* Sector offset in the cluster */
    if ((fp->fptr % SS(fp->fs)) == 0) {     /* On the sector boundary? */
      if (!csect) {             /* On the cluster boundary? */
        clst = (fp->fptr == 0) ?      /* On the top of the file? */
          fp->sclust : get_fat(fp->fs, fp->clust);
        if (clst <= 1) ABORT(fp->fs, FR_INT_ERR);
        if (clst == 0xFFFFFFFF) ABORT(fp->fs, FR_DISK_ERR);
        fp->clust = clst;         /* Update current cluster */
      }
    }
    sect = clust2sect(fp->fs, fp->clust);   /* Get current data sector */
    if (!sect) ABORT(fp->fs, FR_INT_ERR);
    sect += csect;
    if (move_window(fp->fs, sect))        /* Move sector window */
      ABORT(fp->fs, FR_DISK_ERR);
    fp->dsect = sect;
    rcnt = SS(fp->fs) - (WORD)(fp->fptr % SS(fp->fs));  /* Forward data from sector window */
    if (rcnt > btr) rcnt = btr;
    rcnt = (*func)(&fp->fs->win[(WORD)fp->fptr % SS(fp->fs)], rcnt);
    if (!rcnt) ABORT(fp->fs, FR_INT_ERR);
  }

  LEAVE_FF(fp->fs, FR_OK);
}
#endif /* _USE_FORWARD */



#if _USE_MKFS && !_FS_READONLY
/*-----------------------------------------------------------------------*/
/* Create File System on the Drive                                       */
/*-----------------------------------------------------------------------*/
#define N_ROOTDIR 512   /* Number of root dir entries for FAT12/16 */
#define N_FATS    1   /* Number of FAT copies (1 or 2) */


FRESULT f_mkfs (
  BYTE drv,   /* Logical drive number */
  BYTE sfd,   /* Partitioning rule 0:FDISK, 1:SFD */
  UINT au     /* Allocation unit size [bytes] */
)
{
  static const WORD vst[] = { 1024,   512,  256,  128,   64,    32,   16,    8,    4,    2,   0};
  static const WORD cst[] = {32768, 16384, 8192, 4096, 2048, 16384, 8192, 4096, 2048, 1024, 512};
  BYTE fmt, md, sys, *tbl, pdrv, part;
  DWORD n_clst, vs, n, wsect;
  UINT i;
  DWORD b_vol, b_fat, b_dir, b_data;  /* LBA */
  DWORD n_vol, n_rsv, n_fat, n_dir; /* Size */
  FATFS *fs;
  DSTATUS stat;


  /* Check mounted drive and clear work area */
  if (drv >= _VOLUMES) return FR_INVALID_DRIVE;
  if (sfd > 1) return FR_INVALID_PARAMETER;
  if (au & (au - 1)) return FR_INVALID_PARAMETER;
  fs = FatFs[drv];
  if (!fs) return FR_NOT_ENABLED;
  fs->fs_type = 0;
  pdrv = LD2PD(drv);  /* Physical drive */
  part = LD2PT(drv);  /* Partition (0:auto detect, 1-4:get from partition table)*/

  /* Get disk statics */
  stat = disk_initialize(pdrv);
  if (stat & STA_NOINIT) return FR_NOT_READY;
  if (stat & STA_PROTECT) return FR_WRITE_PROTECTED;
#if _MAX_SS != 512          /* Get disk sector size */
  if (disk_ioctl(pdrv, GET_SECTOR_SIZE, &SS(fs)) != RES_OK || SS(fs) > _MAX_SS)
    return FR_DISK_ERR;
#endif
  if (_MULTI_PARTITION && part) {
    /* Get partition information from partition table in the MBR */
    if (disk_read(pdrv, fs->win, 0, 1) != RES_OK) return FR_DISK_ERR;
    if (LD_WORD(fs->win+BS_55AA) != 0xAA55) return FR_MKFS_ABORTED;
    tbl = &fs->win[MBR_Table + (part - 1) * SZ_PTE];
    if (!tbl[4]) return FR_MKFS_ABORTED;  /* No partition? */
    b_vol = LD_DWORD(tbl+8);  /* Volume start sector */
    n_vol = LD_DWORD(tbl+12); /* Volume size */
  } else {
    /* Create a partition in this function */
    if (disk_ioctl(pdrv, GET_SECTOR_COUNT, &n_vol) != RES_OK || n_vol < 128)
      return FR_DISK_ERR;
    b_vol = (sfd) ? 0 : 63;   /* Volume start sector */
    n_vol -= b_vol;       /* Volume size */
  }

  if (!au) {        /* AU auto selection */
    vs = n_vol / (2000 / (SS(fs) / 512));
    for (i = 0; vs < vst[i]; i++) ;
    au = cst[i];
  }
  au /= SS(fs);   /* Number of sectors per cluster */
  if (au == 0) au = 1;
  if (au > 128) au = 128;

  /* Pre-compute number of clusters and FAT syb-type */
  n_clst = n_vol / au;
  fmt = FS_FAT12;
  if (n_clst >= MIN_FAT16) fmt = FS_FAT16;
  if (n_clst >= MIN_FAT32) fmt = FS_FAT32;

  /* Determine offset and size of FAT structure */
  if (fmt == FS_FAT32) {
    n_fat = ((n_clst * 4) + 8 + SS(fs) - 1) / SS(fs);
    n_rsv = 32;
    n_dir = 0;
  } else {
    n_fat = (fmt == FS_FAT12) ? (n_clst * 3 + 1) / 2 + 3 : (n_clst * 2) + 4;
    n_fat = (n_fat + SS(fs) - 1) / SS(fs);
    n_rsv = 1;
    n_dir = (DWORD)N_ROOTDIR * SZ_DIR / SS(fs);
  }
  b_fat = b_vol + n_rsv;        /* FAT area start sector */
  b_dir = b_fat + n_fat * N_FATS;   /* Directory area start sector */
  b_data = b_dir + n_dir;       /* Data area start sector */
  if (n_vol < b_data + au - b_vol) return FR_MKFS_ABORTED;  /* Too small volume */

  /* Align data start sector to erase block boundary (for flash memory media) */
  if (disk_ioctl(pdrv, GET_BLOCK_SIZE, &n) != RES_OK || !n || n > 32768) n = 1;
  n = (b_data + n - 1) & ~(n - 1);  /* Next nearest erase block from current data start */
  n = (n - b_data) / N_FATS;
  if (fmt == FS_FAT32) {    /* FAT32: Move FAT offset */
    n_rsv += n;
    b_fat += n;
  } else {          /* FAT12/16: Expand FAT size */
    n_fat += n;
  }

  /* Determine number of clusters and final check of validity of the FAT sub-type */
  n_clst = (n_vol - n_rsv - n_fat * N_FATS - n_dir) / au;
  if (   (fmt == FS_FAT16 && n_clst < MIN_FAT16)
    || (fmt == FS_FAT32 && n_clst < MIN_FAT32))
    return FR_MKFS_ABORTED;

  switch (fmt) {  /* Determine system ID for partition table */
  case FS_FAT12:  sys = 0x01; break;
  case FS_FAT16:  sys = (n_vol < 0x10000) ? 0x04 : 0x06; break;
  default:    sys = 0x0C;
  }

  if (_MULTI_PARTITION && part) {
    /* Update system ID in the partition table */
    tbl = &fs->win[MBR_Table + (part - 1) * SZ_PTE];
    tbl[4] = sys;
    if (disk_write(pdrv, fs->win, 0, 1) != RES_OK) return FR_DISK_ERR;
    md = 0xF8;
  } else {
    if (sfd) {  /* No patition table (SFD) */
      md = 0xF0;
    } else {  /* Create partition table (FDISK) */
      mem_set(fs->win, 0, SS(fs));
      tbl = fs->win+MBR_Table;  /* Create partiton table for single partition in the drive */
      tbl[1] = 1;           /* Partition start head */
      tbl[2] = 1;           /* Partition start sector */
      tbl[3] = 0;           /* Partition start cylinder */
      tbl[4] = sys;         /* System type */
      tbl[5] = 254;         /* Partition end head */
      n = (b_vol + n_vol) / 63 / 255;
      tbl[6] = (BYTE)((n >> 2) | 63); /* Partiiton end sector */
      tbl[7] = (BYTE)n;       /* End cylinder */
      ST_DWORD(tbl+8, 63);      /* Partition start in LBA */
      ST_DWORD(tbl+12, n_vol);    /* Partition size in LBA */
      ST_WORD(fs->win+BS_55AA, 0xAA55); /* MBR signature */
      if (disk_write(pdrv, fs->win, 0, 1) != RES_OK)  /* Write it to the MBR sector */
        return FR_DISK_ERR;
      md = 0xF8;
    }
  }

  /* Create BPB in the VBR */
  tbl = fs->win;              /* Clear sector */
  mem_set(tbl, 0, SS(fs));
  mem_cpy(tbl, "\xEB\xFE\x90" "MSDOS5.0", 11);/* Boot jump code, OEM name */
  i = SS(fs);               /* Sector size */
  ST_WORD(tbl+BPB_BytsPerSec, i);
  tbl[BPB_SecPerClus] = (BYTE)au;     /* Sectors per cluster */
  ST_WORD(tbl+BPB_RsvdSecCnt, n_rsv);   /* Reserved sectors */
  tbl[BPB_NumFATs] = N_FATS;        /* Number of FATs */
  i = (fmt == FS_FAT32) ? 0 : N_ROOTDIR;  /* Number of rootdir entries */
  ST_WORD(tbl+BPB_RootEntCnt, i);
  if (n_vol < 0x10000) {          /* Number of total sectors */
    ST_WORD(tbl+BPB_TotSec16, n_vol);
  } else {
    ST_DWORD(tbl+BPB_TotSec32, n_vol);
  }
  tbl[BPB_Media] = md;          /* Media descriptor */
  ST_WORD(tbl+BPB_SecPerTrk, 63);     /* Number of sectors per track */
  ST_WORD(tbl+BPB_NumHeads, 255);     /* Number of heads */
  ST_DWORD(tbl+BPB_HiddSec, b_vol);   /* Hidden sectors */
  n = get_fattime();            /* Use current time as VSN */
  if (fmt == FS_FAT32) {
    ST_DWORD(tbl+BS_VolID32, n);    /* VSN */
    ST_DWORD(tbl+BPB_FATSz32, n_fat); /* Number of sectors per FAT */
    ST_DWORD(tbl+BPB_RootClus, 2);    /* Root directory start cluster (2) */
    ST_WORD(tbl+BPB_FSInfo, 1);     /* FSInfo record offset (VBR+1) */
    ST_WORD(tbl+BPB_BkBootSec, 6);    /* Backup boot record offset (VBR+6) */
    tbl[BS_DrvNum32] = 0x80;      /* Drive number */
    tbl[BS_BootSig32] = 0x29;     /* Extended boot signature */
    mem_cpy(tbl+BS_VolLab32, "NO NAME    " "FAT32   ", 19); /* Volume label, FAT signature */
  } else {
    ST_DWORD(tbl+BS_VolID, n);      /* VSN */
    ST_WORD(tbl+BPB_FATSz16, n_fat);  /* Number of sectors per FAT */
    tbl[BS_DrvNum] = 0x80;        /* Drive number */
    tbl[BS_BootSig] = 0x29;       /* Extended boot signature */
    mem_cpy(tbl+BS_VolLab, "NO NAME    " "FAT     ", 19); /* Volume label, FAT signature */
  }
  ST_WORD(tbl+BS_55AA, 0xAA55);     /* Signature (Offset is fixed here regardless of sector size) */
  if (disk_write(pdrv, tbl, b_vol, 1) != RES_OK)  /* Write it to the VBR sector */
    return FR_DISK_ERR;
  if (fmt == FS_FAT32)              /* Write backup VBR if needed (VBR+6) */
    disk_write(pdrv, tbl, b_vol + 6, 1);

  /* Initialize FAT area */
  wsect = b_fat;
  for (i = 0; i < N_FATS; i++) {    /* Initialize each FAT copy */
    mem_set(tbl, 0, SS(fs));      /* 1st sector of the FAT  */
    n = md;               /* Media descriptor byte */
    if (fmt != FS_FAT32) {
      n |= (fmt == FS_FAT12) ? 0x00FFFF00 : 0xFFFFFF00;
      ST_DWORD(tbl+0, n);       /* Reserve cluster #0-1 (FAT12/16) */
    } else {
      n |= 0xFFFFFF00;
      ST_DWORD(tbl+0, n);       /* Reserve cluster #0-1 (FAT32) */
      ST_DWORD(tbl+4, 0xFFFFFFFF);
      ST_DWORD(tbl+8, 0x0FFFFFFF);  /* Reserve cluster #2 for root dir */
    }
    if (disk_write(pdrv, tbl, wsect++, 1) != RES_OK)
      return FR_DISK_ERR;
    mem_set(tbl, 0, SS(fs));      /* Fill following FAT entries with zero */
    for (n = 1; n < n_fat; n++) {   /* This loop may take a time on FAT32 volume due to many single sector writes */
      if (disk_write(pdrv, tbl, wsect++, 1) != RES_OK)
        return FR_DISK_ERR;
    }
  }

  /* Initialize root directory */
  i = (fmt == FS_FAT32) ? au : n_dir;
  do {
    if (disk_write(pdrv, tbl, wsect++, 1) != RES_OK)
      return FR_DISK_ERR;
  } while (--i);

#if _USE_ERASE  /* Erase data area if needed */
  {
    DWORD eb[2];

    eb[0] = wsect; eb[1] = wsect + (n_clst - ((fmt == FS_FAT32) ? 1 : 0)) * au - 1;
    disk_ioctl(pdrv, CTRL_ERASE_SECTOR, eb);
  }
#endif

  /* Create FSInfo if needed */
  if (fmt == FS_FAT32) {
    ST_DWORD(tbl+FSI_LeadSig, 0x41615252);
    ST_DWORD(tbl+FSI_StrucSig, 0x61417272);
    ST_DWORD(tbl+FSI_Free_Count, n_clst - 1); /* Number of free clusters */
    ST_DWORD(tbl+FSI_Nxt_Free, 2);        /* Last allocated cluster# */
    ST_WORD(tbl+BS_55AA, 0xAA55);
    disk_write(pdrv, tbl, b_vol + 1, 1);  /* Write original (VBR+1) */
    disk_write(pdrv, tbl, b_vol + 7, 1);  /* Write backup (VBR+7) */
  }

  return (disk_ioctl(pdrv, CTRL_SYNC, 0) == RES_OK) ? FR_OK : FR_DISK_ERR;
}


#if _MULTI_PARTITION == 2
/*-----------------------------------------------------------------------*/
/* Divide Physical Drive                                                 */
/*-----------------------------------------------------------------------*/

FRESULT f_fdisk (
  BYTE pdrv,      /* Physical drive number */
  const DWORD szt[],  /* Pointer to the size table for each partitions */
  void* work      /* Pointer to the working buffer */
)
{
  UINT i, n, sz_cyl, tot_cyl, b_cyl, e_cyl, p_cyl;
  BYTE s_hd, e_hd, *p, *buf = (BYTE*)work;
  DSTATUS stat;
  DWORD sz_disk, sz_part, s_part;


  stat = disk_initialize(pdrv);
  if (stat & STA_NOINIT) return FR_NOT_READY;
  if (stat & STA_PROTECT) return FR_WRITE_PROTECTED;
  if (disk_ioctl(pdrv, GET_SECTOR_COUNT, &sz_disk)) return FR_DISK_ERR;

  /* Determine CHS in the table regardless of the drive geometry */
  for (n = 16; n < 256 && sz_disk / n / 63 > 1024; n *= 2) ;
  if (n == 256) n--;
  e_hd = n - 1;
  sz_cyl = 63 * n;
  tot_cyl = sz_disk / sz_cyl;

  /* Create partition table */
  mem_set(buf, 0, _MAX_SS);
  p = buf + MBR_Table; b_cyl = 0;
  for (i = 0; i < 4; i++, p += SZ_PTE) {
    p_cyl = (szt[i] <= 100) ? (DWORD)tot_cyl * szt[i] / 100 : szt[i] / sz_cyl;
    if (!p_cyl) continue;
    s_part = (DWORD)sz_cyl * b_cyl;
    sz_part = (DWORD)sz_cyl * p_cyl;
    if (i == 0) { /* Exclude first track of cylinder 0 */
      s_hd = 1;
      s_part += 63; sz_part -= 63;
    } else {
      s_hd = 0;
    }
    e_cyl = b_cyl + p_cyl - 1;
    if (e_cyl >= tot_cyl) return FR_INVALID_PARAMETER;

    /* Set partition table */
    p[1] = s_hd;            /* Start head */
    p[2] = (BYTE)((b_cyl >> 2) + 1);  /* Start sector */
    p[3] = (BYTE)b_cyl;         /* Start cylinder */
    p[4] = 0x06;            /* System type (temporary setting) */
    p[5] = e_hd;            /* End head */
    p[6] = (BYTE)((e_cyl >> 2) + 63); /* End sector */
    p[7] = (BYTE)e_cyl;         /* End cylinder */
    ST_DWORD(p + 8, s_part);      /* Start sector in LBA */
    ST_DWORD(p + 12, sz_part);      /* Partition size */

    /* Next partition */
    b_cyl += p_cyl;
  }
  ST_WORD(p, 0xAA55);

  /* Write it to the MBR */
  return (disk_write(pdrv, buf, 0, 1) || disk_ioctl(pdrv, CTRL_SYNC, 0)) ? FR_DISK_ERR : FR_OK;
}


#endif /* _MULTI_PARTITION == 2 */
#endif /* _USE_MKFS && !_FS_READONLY */




#if _USE_STRFUNC
/*-----------------------------------------------------------------------*/
/* Get a string from the file                                            */
/*-----------------------------------------------------------------------*/
TCHAR* f_gets (
  TCHAR* buff,  /* Pointer to the string buffer to read */
  int len,    /* Size of string buffer (characters) */
  FIL* fil    /* Pointer to the file object */
)
{
  int n = 0;
  TCHAR c, *p = buff;
  BYTE s[2];
  UINT rc;


  while (n < len - 1) {     /* Read bytes until buffer gets filled */
    f_read(fil, s, 1, &rc);
    if (rc != 1) break;     /* Break on EOF or error */
    c = s[0];
#if _LFN_UNICODE          /* Read a character in UTF-8 encoding */
    if (c >= 0x80) {
      if (c < 0xC0) continue; /* Skip stray trailer */
      if (c < 0xE0) {     /* Two-byte sequense */
        f_read(fil, s, 1, &rc);
        if (rc != 1) break;
        c = ((c & 0x1F) << 6) | (s[0] & 0x3F);
        if (c < 0x80) c = '?';
      } else {
        if (c < 0xF0) {   /* Three-byte sequense */
          f_read(fil, s, 2, &rc);
          if (rc != 2) break;
          c = (c << 12) | ((s[0] & 0x3F) << 6) | (s[1] & 0x3F);
          if (c < 0x800) c = '?';
        } else {      /* Reject four-byte sequense */
          c = '?';
        }
      }
    }
#endif
#if _USE_STRFUNC >= 2
    if (c == '\r') continue;  /* Strip '\r' */
#endif
    *p++ = c;
    n++;
    if (c == '\n') break;   /* Break on EOL */
  }
  *p = 0;
  return n ? buff : 0;      /* When no data read (eof or error), return with error. */
}



#if !_FS_READONLY
#include <stdarg.h>
/*-----------------------------------------------------------------------*/
/* Put a character to the file                                           */
/*-----------------------------------------------------------------------*/
int f_putc (
  TCHAR c,  /* A character to be output */
  FIL* fil  /* Pointer to the file object */
)
{
  UINT bw, btw;
  BYTE s[3];


#if _USE_STRFUNC >= 2
  if (c == '\n') f_putc ('\r', fil);  /* LF -> CRLF conversion */
#endif

#if _LFN_UNICODE  /* Write the character in UTF-8 encoding */
  if (c < 0x80) {     /* 7-bit */
    s[0] = (BYTE)c;
    btw = 1;
  } else {
    if (c < 0x800) {  /* 11-bit */
      s[0] = (BYTE)(0xC0 | (c >> 6));
      s[1] = (BYTE)(0x80 | (c & 0x3F));
      btw = 2;
    } else {      /* 16-bit */
      s[0] = (BYTE)(0xE0 | (c >> 12));
      s[1] = (BYTE)(0x80 | ((c >> 6) & 0x3F));
      s[2] = (BYTE)(0x80 | (c & 0x3F));
      btw = 3;
    }
  }
#else       /* Write the character without conversion */
  s[0] = (BYTE)c;
  btw = 1;
#endif
  f_write(fil, s, btw, &bw);    /* Write the char to the file */
  return (bw == btw) ? 1 : EOF; /* Return the result */
}




/*-----------------------------------------------------------------------*/
/* Put a string to the file                                              */
/*-----------------------------------------------------------------------*/
int f_puts (
  const TCHAR* str, /* Pointer to the string to be output */
  FIL* fil      /* Pointer to the file object */
)
{
  int n;


  for (n = 0; *str; str++, n++) {
    if (f_putc(*str, fil) == EOF) return EOF;
  }
  return n;
}




/*-----------------------------------------------------------------------*/
/* Put a formatted string to the file                                    */
/*-----------------------------------------------------------------------*/
int f_printf (
  FIL* fil,     /* Pointer to the file object */
  const TCHAR* str, /* Pointer to the format string */
  ...         /* Optional arguments... */
)
{
  va_list arp;
  BYTE f, r;
  UINT i, j, w;
  ULONG v;
  TCHAR c, d, s[16], *p;
  int res, chc, cc;


  va_start(arp, str);

  for (cc = res = 0; cc != EOF; res += cc) {
    c = *str++;
    if (c == 0) break;      /* End of string */
    if (c != '%') {       /* Non escape character */
      cc = f_putc(c, fil);
      if (cc != EOF) cc = 1;
      continue;
    }
    w = f = 0;
    c = *str++;
    if (c == '0') {       /* Flag: '0' padding */
      f = 1; c = *str++;
    } else {
      if (c == '-') {     /* Flag: left justified */
        f = 2; c = *str++;
      }
    }
    while (IsDigit(c)) {    /* Precision */
      w = w * 10 + c - '0';
      c = *str++;
    }
    if (c == 'l' || c == 'L') { /* Prefix: Size is long int */
      f |= 4; c = *str++;
    }
    if (!c) break;
    d = c;
    if (IsLower(d)) d -= 0x20;
    switch (d) {        /* Type is... */
    case 'S' :          /* String */
      p = va_arg(arp, TCHAR*);
      for (j = 0; p[j]; j++) ;
      chc = 0;
      if (!(f & 2)) {
        while (j++ < w) chc += (cc = f_putc(' ', fil));
      }
      chc += (cc = f_puts(p, fil));
      while (j++ < w) chc += (cc = f_putc(' ', fil));
      if (cc != EOF) cc = chc;
      continue;
    case 'C' :          /* Character */
      cc = f_putc((TCHAR)va_arg(arp, int), fil); continue;
    case 'B' :          /* Binary */
      r = 2; break;
    case 'O' :          /* Octal */
      r = 8; break;
    case 'D' :          /* Signed decimal */
    case 'U' :          /* Unsigned decimal */
      r = 10; break;
    case 'X' :          /* Hexdecimal */
      r = 16; break;
    default:          /* Unknown type (passthrough) */
      cc = f_putc(c, fil); continue;
    }

    /* Get an argument and put it in numeral */
    v = (f & 4) ? (ULONG)va_arg(arp, long) : ((d == 'D') ? (ULONG)(long)va_arg(arp, int) : (ULONG)va_arg(arp, unsigned int));
    if (d == 'D' && (v & 0x80000000)) {
      v = 0 - v;
      f |= 8;
    }
    i = 0;
    do {
      d = (TCHAR)(v % r); v /= r;
      if (d > 9) d += (c == 'x') ? 0x27 : 0x07;
      s[i++] = d + '0';
    } while (v && i < sizeof(s) / sizeof(s[0]));
    if (f & 8) s[i++] = '-';
    j = i; d = (f & 1) ? '0' : ' ';
    res = 0;
    while (!(f & 2) && j++ < w) res += (cc = f_putc(d, fil));
    do res += (cc = f_putc(s[--i], fil)); while(i);
    while (j++ < w) res += (cc = f_putc(' ', fil));
    if (cc != EOF) cc = res;
  }

  va_end(arp);
  return (cc == EOF) ? cc : res;
}

#endif /* !_FS_READONLY */
#endif /* _USE_STRFUNC */

